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Bibliography on: Evolution of Multicelluarity

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ESP: PubMed Auto Bibliography 12 Aug 2022 at 01:41 Created: 

Evolution of Multicelluarity

Created with PubMed® Query: (evolution OR origin) AND (multicellularity OR multicellular) NOT 33634751[PMID] NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)

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RevDate: 2022-08-10

Kim H, Skinner DJ, Glass DS, et al (2022)

4-bit adhesion logic enables universal multicellular interface patterning.

Nature, 608(7922):324-329.

Multicellular systems, from bacterial biofilms to human organs, form interfaces (or boundaries) between different cell collectives to spatially organize versatile functions1,2. The evolution of sufficiently descriptive genetic toolkits probably triggered the explosion of complex multicellular life and patterning3,4. Synthetic biology aims to engineer multicellular systems for practical applications and to serve as a build-to-understand methodology for natural systems5-8. However, our ability to engineer multicellular interface patterns2,9 is still very limited, as synthetic cell-cell adhesion toolkits and suitable patterning algorithms are underdeveloped5,7,10-13. Here we introduce a synthetic cell-cell adhesin logic with swarming bacteria and establish the precise engineering, predictive modelling and algorithmic programming of multicellular interface patterns. We demonstrate interface generation through a swarming adhesion mechanism, quantitative control over interface geometry and adhesion-mediated analogues of developmental organizers and morphogen fields. Using tiling and four-colour-mapping concepts, we identify algorithms for creating universal target patterns. This synthetic 4-bit adhesion logic advances practical applications such as human-readable molecular diagnostics, spatial fluid control on biological surfaces and programmable self-growing materials5-8,14. Notably, a minimal set of just four adhesins represents 4 bits of information that suffice to program universal tessellation patterns, implying a low critical threshold for the evolution and engineering of complex multicellular systems3,5.

RevDate: 2022-08-10

Chen M, Teng W, Zhao L, et al (2022)

Phylogenomics uncovers evolutionary trajectory of nitrogen fixation in Cyanobacteria.

Molecular biology and evolution pii:6659242 [Epub ahead of print].

Biological nitrogen fixation (BNF) by cyanobacteria is of significant importance for the Earth's biogeochemical nitrogen cycle but is restricted to a few genera that do not form monophyletic group. To explore the evolutionary trajectory of BNF and investigate the driving forces of its evolution, we analyze 650 cyanobacterial genomes and compile the database of diazotrophic cyanobacteria based on the presence of nitrogen fixation gene clusters (NFGCs). We report that 266 out of 650 examined genomes are NFGC-carrying members, and these potentially diazotrophic cyanobacteria are unevenly distributed across the phylogeny of Cyanobacteria, that multiple independent losses shaped the scattered distribution. Among the diazotrophic cyanobacteria, two types of NFGC exist, with one being ancestral and abundant, which have descended from diazotrophic ancestors, and the other being anaerobe-like and sparse, possibly being acquired from anaerobic microbes through horizontal gene transfer. Interestingly, we illustrate that the origin of BNF in Cyanobacteria coincide with two major evolutionary events. One is the origin of multicellularity of cyanobacteria, the other is concurrent genetic innovations with massive gene gains and expansions, implicating their key roles in triggering the evolutionary transition from nondiazotrophic to diazotrophic cyanobacteria. Additionally, we reveal that genes involved in accelerating respiratory electron transport (coxABC), anoxygenic photosynthetic electron transport (sqr), as well as anaerobic metabolisms (pfor, hemN, nrdG, adhE) are enriched in diazotrophic cyanobacteria, representing adaptive genetic signatures that underpin the diazotrophic lifestyle. Collectively, our study suggests that multicellularity, together with concurrent genetic adaptations contribute to the evolution of diazotrophic cyanobacteria.

RevDate: 2022-08-08

Sartor F, ÁT Kovács (2022)

Rhythmic Spatial Self-Organization of Bacterial Colonies.

mBio [Epub ahead of print].

Bacteria display a remarkable capacity to organize themselves in space and time within biofilms. Traditionally, the spatial organization of biofilms has been dissected vertically; however, biofilms can exhibit complex, temporally structured, two-dimensional radial patterns while spreading on a surface. Kahl and colleagues report a ring pattern that indicates the alternating redox metabolism of P. aeruginosa biofilms under light/dark cycles. Does the presence of a rhythmic, daily phenotype imply a circadian rhythm? Here, we highlight several examples of rhythmic patterns reported in the literature for surface-colonizing multicellular assemblies and discuss the conceptual requirements for proving the presence of a prokaryotic circadian clock behind pattern formation.

RevDate: 2022-07-19

Chakravarty AK, McGrail DJ, Lozanoski TM, et al (2022)

Biomolecular Condensation: A New Phase in Cancer Research.

Cancer discovery pii:707061 [Epub ahead of print].

Multicellularity was a watershed development in evolution. However, it also meant that individual cells could escape regulatory mechanisms that restrict proliferation at a severe cost to the organism: cancer. From the standpoint of cellular organization, evolutionary complexity scales to organize different molecules within the intracellular milieu. The recent realization that many biomolecules can "phase-separate" into membraneless organelles, reorganizing cellular biochemistry in space and time, has led to an explosion of research activity in this area. In this review, we explore mechanistic connections between phase separation and cancer-associated processes and emerging examples of how these become deranged in malignancy.

SIGNIFICANCE: One of the fundamental functions of phase separation is to rapidly and dynamically respond to environmental perturbations. Importantly, these changes often lead to alterations in cancer-relevant pathways and processes. This review covers recent advances in the field, including emerging principles and mechanisms of phase separation in cancer.

RevDate: 2022-07-28

Raguž L, Peng CC, Rutaganira FUN, et al (2022)

Total Synthesis and Functional Evaluation of IORs, Sulfonolipid-based Inhibitors of Cell Differentiation in Salpingoeca rosetta.

Angewandte Chemie (International ed. in English) [Epub ahead of print].

The choanoflagellate Salpingoeca rosetta is an important model system to study the evolution of multicellularity. In this study we developed a new, modular and scalable synthesis of sulfonolipid IOR-1A (six steps, 27% overall yield), which acts as bacterial inhibitor of rosette formation in S. rosetta . The synthesis features a decarboxylative cross-coupling reaction of a sulfonic acid-containing tartaric acid derivative with alkyl zinc reagents. Synthesis of 15 modified IOR-1A derivatives, including fluorescent and photoaffinity-based probes, allowed quantification of IOR-1A, localization studies within S. rosetta cells and evaluation of structure-activity relations. In a proof of concept study, an inhibitory bifunctional probe was employed in proteomic profiling studies, which allowed to deduce binding partners in bacteria and S. rosetta . These results showcase the power of synthetic chemistry to decipher the biochemical basis of cell differentiation processes within S. rosetta .

RevDate: 2022-07-28
CmpDate: 2022-07-28

Meléndez García R, Haccard O, Chesneau A, et al (2022)

A non-transcriptional function of Yap regulates the DNA replication program in Xenopus laevis.

eLife, 11: pii:75741.

In multicellular eukaryotic organisms, the initiation of DNA replication occurs asynchronously throughout S-phase according to a regulated replication timing program. Here, using Xenopus egg extracts, we showed that Yap (Yes-associated protein 1), a downstream effector of the Hippo signalling pathway, is required for the control of DNA replication dynamics. We found that Yap is recruited to chromatin at the start of DNA replication and identified Rif1, a major regulator of the DNA replication timing program, as a novel Yap binding protein. Furthermore, we show that either Yap or Rif1 depletion accelerates DNA replication dynamics by increasing the number of activated replication origins. In Xenopus embryos, using a Trim-Away approach during cleavage stages devoid of transcription, we found that either Yap or Rif1 depletion triggers an acceleration of cell divisions, suggesting a shorter S-phase by alterations of the replication program. Finally, our data show that Rif1 knockdown leads to defects in the partitioning of early versus late replication foci in retinal stem cells, as we previously showed for Yap. Altogether, our findings unveil a non-transcriptional role for Yap in regulating replication dynamics. We propose that Yap and Rif1 function as brakes to control the DNA replication program in early embryos and post-embryonic stem cells.

RevDate: 2022-07-27

Le Gloanec C, Collet L, Silveira SR, et al (2022)

Cell type-specific dynamics underlie cellular growth variability in plants.

Development (Cambridge, England), 149(14):.

Coordination of growth, patterning and differentiation is required for shaping organs in multicellular organisms. In plants, cell growth is controlled by positional information, yet the behavior of individual cells is often highly heterogeneous. The origin of this variability is still unclear. Using time-lapse imaging, we determined the source and relevance of cellular growth variability in developing organs of Arabidopsis thaliana. We show that growth is more heterogeneous in the leaf blade than in the midrib and petiole, correlating with higher local differences in growth rates between neighboring cells in the blade. This local growth variability coincides with developing stomata. Stomatal lineages follow a specific, time-dependent growth program that is different from that of their surroundings. Quantification of cellular dynamics in the leaves of a mutant lacking stomata, as well as analysis of floral organs, supports the idea that growth variability is mainly driven by stomata differentiation. Thus, the cell-autonomous behavior of specialized cells is the main source of local growth variability in otherwise homogeneously growing tissue. Those growth differences are buffered by the immediate neighbors of stomata and trichomes to achieve robust organ shapes.

RevDate: 2022-07-27

Dijkwel Y, DJ Tremethick (2022)

The Role of the Histone Variant H2A.Z in Metazoan Development.

Journal of developmental biology, 10(3): pii:jdb10030028.

During the emergence and radiation of complex multicellular eukaryotes from unicellular ancestors, transcriptional systems evolved by becoming more complex to provide the basis for this morphological diversity. The way eukaryotic genomes are packaged into a highly complex structure, known as chromatin, underpins this evolution of transcriptional regulation. Chromatin structure is controlled by a variety of different epigenetic mechanisms, including the major mechanism for altering the biochemical makeup of the nucleosome by replacing core histones with their variant forms. The histone H2A variant H2A.Z is particularly important in early metazoan development because, without it, embryos cease to develop and die. However, H2A.Z is also required for many differentiation steps beyond the stage that H2A.Z-knockout embryos die. H2A.Z can facilitate the activation and repression of genes that are important for pluripotency and differentiation, and acts through a variety of different molecular mechanisms that depend upon its modification status, its interaction with histone and nonhistone partners, and where it is deposited within the genome. In this review, we discuss the current knowledge about the different mechanisms by which H2A.Z regulates chromatin function at various developmental stages and the chromatin remodeling complexes that determine when and where H2A.Z is deposited.

RevDate: 2022-07-26

Lyng M, ÁT Kovács (2022)

Microbial ecology: Metabolic heterogeneity and the division of labor in multicellular structures.

Current biology : CB, 32(14):R771-R774.

Many bacterial species are capable of differentiating to create phenotypic heterogeneity. Using the aggregate-forming marine bacterium Vibrio splendidus, a new study reveals how this organism differentiates to form spherical structures with a motile, carbon-storing core and a non-motile shell.

RevDate: 2022-07-25

Ní Leathlobhair M, RE Lenski (2022)

Population genetics of clonally transmissible cancers.

Nature ecology & evolution [Epub ahead of print].

Populations of cancer cells are subject to the same core evolutionary processes as asexually reproducing, unicellular organisms. Transmissible cancers are particularly striking examples of these processes. These unusual cancers are clonal lineages that can spread through populations via physical transfer of living cancer cells from one host individual to another, and they have achieved long-term success in the colonization of at least eight different host species. Population genetic theory provides a useful framework for understanding the shift from a multicellular sexual animal into a unicellular asexual clone and its long-term effects on the genomes of these cancers. In this Review, we consider recent findings from transmissible cancer research with the goals of developing an evolutionarily informed perspective on transmissible cancers, examining possible implications for their long-term fate and identifying areas for future research on these exceptional lineages.

RevDate: 2022-07-21

Nies F, Springstein BL, Hanke DM, et al (2022)

Natural Competence in the Filamentous, Heterocystous Cyanobacterium Chlorogloeopsis fritschii PCC 6912.

mSphere [Epub ahead of print].

Lateral gene transfer plays an important role in the evolution of genetic diversity in prokaryotes. DNA transfer via natural transformation depends on the ability of recipient cells to actively transport DNA from the environment into the cytoplasm, termed natural competence, which relies on the presence of type IV pili and other competence proteins. Natural competence has been described in cyanobacteria for several organisms, including unicellular and filamentous species. However, natural competence in cyanobacteria that differentiate specialized cells for N2-fixation (heterocysts) and form branching or multiseriate cell filaments (termed subsection V) remains unknown. Here, we show that genes essential for natural competence are conserved in subsection V cyanobacteria. Furthermore, using the replicating plasmid pRL25C, we experimentally demonstrate natural competence in a subsection V organism: Chlorogloeopsis fritschii PCC 6912. Our results suggest that natural competence is a common trait in cyanobacteria forming complex cell filament morphologies. IMPORTANCE Cyanobacteria are crucial players in the global biogeochemical cycles, where they contribute to CO2- and N2-fixation. Their main ecological significance is the primary biomass production owing to oxygenic photosynthesis. Cyanobacteria are a diverse phylum, in which the most complex species differentiate specialized cell types and form true-branching or multiseriate cell filament structures (termed subsection V cyanobacteria). These bacteria are considered a peak in the evolution of prokaryotic multicellularity. Among others, species in that group inhabit fresh and marine water habitats, soil, and extreme habitats such as thermal springs. Here, we show that the core genes required for natural competence are frequent in subsection V cyanobacteria and demonstrate for the first time natural transformation in a member of subsection V. The prevalence of natural competence has implications for the role of DNA acquisition in the genome evolution of cyanobacteria. Furthermore, the presence of mechanisms for natural transformation opens up new possibilities for the genetic modification of subsection V cyanobacteria.

RevDate: 2022-07-21

Howe J, Rink JC, Wang B, et al (2022)

Multicellularity in animals: The potential for within-organism conflict.

Proceedings of the National Academy of Sciences of the United States of America, 119(32):e2120457119.

Metazoans function as individual organisms but also as "colonies" of cells whose single-celled ancestors lived and reproduced independently. Insights from evolutionary biology about multicellular group formation help us understand the behavior of cells: why they cooperate, and why cooperation sometimes breaks down. Current explanations for multicellularity focus on two aspects of development which promote cooperation and limit conflict among cells: a single-cell bottleneck, which creates organisms composed of clones, and a separation of somatic and germ cell lineages, which reduces the selective advantage of cheating. However, many obligately multicellular organisms thrive with neither, creating the potential for within-organism conflict. Here, we argue that the prevalence of such organisms throughout the Metazoa requires us to refine our preconceptions of conflict-free multicellularity. Evolutionary theory must incorporate developmental mechanisms across a broad range of organisms-such as unusual reproductive strategies, totipotency, and cell competition-while developmental biology must incorporate evolutionary principles. To facilitate this cross-disciplinary approach, we provide a conceptual overview from evolutionary biology for developmental biologists, using analogous examples in the well-studied social insects.

RevDate: 2022-07-19

Arjoca S, Robu A, Neagu M, et al (2022)

Mathematical and computational models in spheroid-based biofabrication.

Acta biomaterialia pii:S1742-7061(22)00418-4 [Epub ahead of print].

Ubiquitous in embryonic development, tissue fusion is of interest to tissue engineers who use tissue spheroids or organoids as building blocks of three-dimensional (3D) multicellular constructs. This review presents mathematical models and computer simulations of the fusion of tissue spheroids. The motivation of this study stems from the need to predict the post-printing evolution of 3D bioprinted constructs. First, we provide a brief overview of differential adhesion, the main morphogenetic mechanism involved in post-printing structure formation. It will be shown that clusters of cohesive cells behave as an incompressible viscous fluid on the time scale of hours. The discussion turns then to mathematical models based on the continuum hydrodynamics of highly viscous liquids and on statistical mechanics. Next, we analyze the validity and practical use of computational models of multicellular self-assembly in live constructs created by tissue spheroid bioprinting. Finally, we discuss the perspectives of the field as machine learning starts to reshape experimental design, and modular robotic workstations tend to alleviate the burden of repetitive tasks in biofabrication. STATEMENT OF SIGNIFICANCE: : Bioprinted constructs are living systems, which evolve via morphogenetic mechanisms known from developmental biology. This review presents mathematical and computational tools devised for modeling post-printing structure formation. They help achieving a desirable outcome without expensive optimization experiments. While previous reviews mainly focused on assumptions, technical details, strengths, and limitations of computational models of multicellular self-assembly, this article discusses their validity and practical use in biofabrication. It also presents an overview of mathematical models that proved to be useful in the evaluation of experimental data on tissue spheroid fusion, and in the calibration of computational models. Finally, the perspectives of the field are discussed in the advent of robotic biofabrication platforms and bioprinting process optimization by machine learning.

RevDate: 2022-07-20

Belcher LJ, Madgwick PG, Kuwana S, et al (2022)

Developmental constraints enforce altruism and avert the tragedy of the commons in a social microbe.

Proceedings of the National Academy of Sciences of the United States of America, 119(29):e2111233119.

Organisms often cooperate through the production of freely available public goods. This can greatly benefit the group but is vulnerable to the "tragedy of the commons" if individuals lack the motivation to make the necessary investment into public goods production. Relatedness to groupmates can motivate individual investment because group success ultimately benefits their genes' own self-interests. However, systems often lack mechanisms that can reliably ensure that relatedness is high enough to promote cooperation. Consequently, groups face a persistent threat from the tragedy unless they have a mechanism to enforce investment when relatedness fails to provide adequate motivation. To understand the real threat posed by the tragedy and whether groups can avert its impact, we determine how the social amoeba Dictyostelium discoideum responds as relatedness decreases to levels that should induce the tragedy. We find that, while investment in public goods declines as overall within-group relatedness declines, groups avert the expected catastrophic collapse of the commons by continuing to invest, even when relatedness should be too low to incentivize any contribution. We show that this is due to a developmental buffering system that generates enforcement because insufficient cooperation perturbs the balance of a negative feedback system controlling multicellular development. This developmental constraint enforces investment under the conditions expected to be most tragic, allowing groups to avert a collapse in cooperation. These results help explain how mechanisms that suppress selfishness and enforce cooperation can arise inadvertently as a by-product of constraints imposed by selection on different traits.

RevDate: 2022-07-21
CmpDate: 2022-07-20

Passer AR, Clancey SA, Shea T, et al (2022)

Obligate sexual reproduction of a homothallic fungus closely related to the Cryptococcus pathogenic species complex.

eLife, 11:.

eLife digest.

Fungi are enigmatic organisms that flourish in soil, on decaying plants, or during infection of animals or plants. Growing in myriad forms, from single-celled yeast to multicellular molds and mushrooms, fungi have also evolved a variety of strategies to reproduce. Normally, fungi reproduce in one of two ways: either they reproduce asexually, with one individual producing a new individual identical to itself, or they reproduce sexually, with two individuals of different 'mating types' contributing to produce a new individual. However, individuals of some species exhibit 'homothallism' or self-fertility: these individuals can produce reproductive cells that are universally compatible, and therefore can reproduce sexually with themselves or with any other cell in the population.

Homothallism has evolved multiple times throughout the fungal kingdom, suggesting it confers advantage when population numbers are low or mates are hard to find. Yet some homothallic fungi been overlooked compared to heterothallic species, whose mating types have been well characterised. Understanding the genetic basis of homothallism and how it evolved in different species can provide insights into pathogenic species that cause fungal disease.

With that in mind, Passer, Clancey et al. explored the genetic basis of homothallism in Cryptococcus depauperatus, a close relative of C. neoformans, a species that causes fungal infections in humans. A combination of genetic sequencing techniques and experiments were applied to analyse, compare, and manipulate C. depauperatus' genome to see how this species evolved self-fertility.

Passer, Clancey et al. showed that C. depauperatus evolved the ability to reproduce sexually by itself via a unique evolutionary pathway. The result is a form of homothallism never reported in fungi before. C. depauperatus lost some of the genes that control mating in other species of fungi, and acquired genes from the opposing mating types of a heterothallic ancestor to become self-fertile.

Passer, Clancey et al. also found that, unlike other Cryptococcus species that switch between asexual and sexual reproduction, C. depauperatus grows only as long, branching filaments called hyphae, a sexual form. The species reproduces sexually with itself throughout its life cycle and is unable to produce a yeast (asexual) form, in contrast to other closely related species.

This work offers new insights into how different modes of sexual reproduction have evolved in fungi. It also provides another interesting case of how genome plasticity and evolutionary pressures can produce similar outcomes, homothallism, via different evolutionary paths. Lastly, assembling the complete genome of C. depauperatus will foster comparative studies between pathogenic and non-pathogenic Cryptococcus species.

RevDate: 2022-07-18

Wu TY, Hoh KL, Boonyaves K, et al (2022)

Diversification of heat shock transcription factors expanded thermal stress responses during early plant evolution.

The Plant cell pii:6645776 [Epub ahead of print].

The copy numbers of many plant transcription factor (TF) genes substantially increased during terrestrialization. This allowed TFs to acquire new specificities and thus create gene regulatory networks (GRNs) with new biological functions to help plants adapt to terrestrial environments. Through characterizing Heat Shock Factor (HSF) genes MpHSFA1 and MpHSFB1 in the liverwort Marchantia polymorpha, we explored how heat-responsive GRNs widened their functions in M. polymorpha and Arabidopsis thaliana. An interspecies comparison of heat-induced transcriptomes and the evolutionary rates of HSFs demonstrated the emergence and subsequent rapid evolution of HSFB prior to terrestrialization. Transcriptome and metabolome analyses of M. polymorpha HSF-null mutants revealed that MpHSFA1 controls canonical heat responses such as thermotolerance and metabolic changes. MpHSFB1 also plays essential roles in heat responses, as well as regulating developmental processes including meristem branching and antheridiophore formation. Analysis of cis-regulatory elements revealed development- and stress-related TFs that function directly or indirectly downstream of HSFB. Male gametophytes of M. polymorpha showed higher levels of thermotolerance than female gametophytes, which could be explained by different expression levels of MpHSFA1U and MpHSFA1V on sex chromosome. We propose that the diversification of HSFs is linked to the expansion of HS responses, which enabled coordinated multicellular reactions in land plants.

RevDate: 2022-07-16

Gabaldón T, Völcker E, G Torruella (2022)

On the Biology, Diversity and Evolution of Nucleariid Amoebae (Amorphea, Obazoa, Opisthokonta1.

Protist, 173(4):125895 pii:S1434-4610(22)00040-2 [Epub ahead of print].

Nucleariids are a small group of free-living heterotrophic amoebae. Although these organisms present a variety of cell sizes and cell coverings, they are mostly spherical cells with radiating filopodia, sometimes with several nuclei. Nuclearia, the genus that gives the name to the group, contains species that are opportunistic consumers of detritus, bacteria, and algae. The beautiful Pompholyxophrys is covered with endogenous siliceous pearls. Lithocolla covers itself with sand particles, or otherwise diatom frustules. The tiny Parvularia exclusively feeds on bacteria, and Fonticula is adapted to solid substrates and presents aggregative multicellular stages. Nucleariids belong to the Opisthokonta, which comprise animals, fungi, and their protist relatives, and form the earliest branch in the holomycotan clade (fungi and closest relatives). Hence, they are key for understanding the origin and diversification of Opisthokonta, an eukaryotic supergroup that contains organisms with different feeding modes, life-styles, and cell organizations. In this review, the reader will find an introduction to nucleariids, from their discovery in the 19th century until the most recent studies. It summarizes available information on their morphology, life history, cell organisation, ecology, diversity, systematics and evolution.

RevDate: 2022-07-13

Salnikov L, MG Baramiya (2020)

The Ratio of the Genome Two Functional Parts Activity as the Prime Cause of Aging.

Frontiers in aging, 1:608076 pii:608076.

The metazoan genome composes of sets of housekeeping genes (HG) for fundamental cellular autonomous processes and integrative genes (IntG) that provide integrative functions and form the body as an integrated whole. The main paradigm for multicellularity development which has been improved in evolution, is the submission of the cellular autonomy to the interests of the integrated whole. Permanent increase of the "functional tax" of IntG-genome (IntG-shift) and epigenetic restriction of autonomy in phylogenesis/ontogenesis is the essence and root cause of aging, inherent in the very nature of highly integrated multicellularity. The regulation of the balance shift toward HG can be managed to eliminate aging and avoid carcinogenesis, which is only due to the irreversibility of this shift. Here we propose the criterion for measuring the functional and biological age of cells and the body as a whole for assessing the effectiveness of any type of palliative geroprotective or radical anti-aging intervention.

RevDate: 2022-07-05

Beljan S, Dominko K, Talajić A, et al (2022)

Structure and function of cancer-related developmentally regulated GTP-binding protein 1 (DRG1) is conserved between sponges and humans.

Scientific reports, 12(1):11379.

Cancer is a disease caused by errors within the multicellular system and it represents a major health issue in multicellular organisms. Although cancer research has advanced substantially, new approaches focusing on fundamental aspects of cancer origin and mechanisms of spreading are necessary. Comparative genomic studies have shown that most genes linked to human cancer emerged during the early evolution of Metazoa. Thus, basal animals without true tissues and organs, such as sponges (Porifera), might be an innovative model system for understanding the molecular mechanisms of proteins involved in cancer biology. One of these proteins is developmentally regulated GTP-binding protein 1 (DRG1), a GTPase stabilized by interaction with DRG family regulatory protein 1 (DFRP1). This study reveals a high evolutionary conservation of DRG1 gene/protein in metazoans. Our biochemical analysis and structural predictions show that both recombinant sponge and human DRG1 are predominantly monomers that form complexes with DFRP1 and bind non-specifically to RNA and DNA. We demonstrate the conservation of sponge and human DRG1 biological features, including intracellular localization and DRG1:DFRP1 binding, function of DRG1 in α-tubulin dynamics, and its role in cancer biology demonstrated by increased proliferation, migration and colonization in human cancer cells. These results suggest that the ancestor of all Metazoa already possessed DRG1 that is structurally and functionally similar to the human DRG1, even before the development of real tissues or tumors, indicating an important function of DRG1 in fundamental cellular pathways.

RevDate: 2022-07-01

Kaluthantrige Don F, N Kalebic (2022)

Forebrain Organoids to Model the Cell Biology of Basal Radial Glia in Neurodevelopmental Disorders and Brain Evolution.

Frontiers in cell and developmental biology, 10:917166 pii:917166.

The acquisition of higher intellectual abilities that distinguish humans from their closest relatives correlates greatly with the expansion of the cerebral cortex. This expansion is a consequence of an increase in neuronal cell production driven by the higher proliferative capacity of neural progenitor cells, in particular basal radial glia (bRG). Furthermore, when the proliferation of neural progenitor cells is impaired and the final neuronal output is altered, severe neurodevelopmental disorders can arise. To effectively study the cell biology of human bRG, genetically accessible human experimental models are needed. With the pioneering success to isolate and culture pluripotent stem cells in vitro, we can now routinely investigate the developing human cerebral cortex in a dish using three-dimensional multicellular structures called organoids. Here, we will review the molecular and cell biological features of bRG that have recently been elucidated using brain organoids. We will further focus on the application of this simple model system to study in a mechanistically actionable way the molecular and cellular events in bRG that can lead to the onset of various neurodevelopmental diseases.

RevDate: 2022-06-27

Chen S, Yu M, Zhang W, et al (2022)

Metagenomic and Microscopic Analysis of Magnetotactic Bacteria in Tangyin Hydrothermal Field of Okinawa Trough.

Frontiers in microbiology, 13:887136.

Magnetotactic bacteria (MTB) have been found in a wide variety of marine habitats, ranging from intertidal sediments to deep-sea seamounts. Deep-sea hydrothermal fields are rich in metal sulfides, which are suitable areas for the growth of MTB. However, MTB in hydrothermal fields have never been reported. Here, the presence of MTB in sediments from the Tangyin hydrothermal field was analyzed by 16S rRNA gene amplicon analysis, metagenomics, and transmission electron microscopy. Sequencing 16S rRNA gene yielded a total of 709 MTB sequences belonging to 20 OTUs, affiliated with Desulfobacterota, Alphaproteobacteria, and Nitrospirae. Three shapes of magnetofossil were identified by transmission electron microscopy: elongated-prismatic, bullet-shaped, and cuboctahedron. All of these structures were composed of Fe3O4. A total of 121 sequences were found to be homologous to the published MTB magnetosome-function-related genes, and relevant domains were identified. Further analysis revealed that diverse MTB are present in the Tangyin hydrothermal field, and that multicellular magnetotactic prokaryote (MMPs) might be the dominant MTB.

RevDate: 2022-06-27

Wang H, Umer MJ, Liu F, et al (2022)

Genome-Wide Identification and Characterization of CPR5 Genes in Gossypium Reveals Their Potential Role in Trichome Development.

Frontiers in genetics, 13:921096 pii:921096.

Trichomes protect plants against insects, microbes, herbivores, and abiotic damages and assist seed dispersal. The function of CPR5 genes have been found to be involved in the trichome development but the research on the underlying genetic and molecular mechanisms are extremely limited. Herein, genome wide identification and characterization of CPR5 genes was performed. In total, 26 CPR5 family members were identified in Gossypium species. Phylogenetic analysis, structural characteristics, and synteny analysis of CPR5s showed the conserved evolution relationships of CPR5. The promoter analysis of CPR5 genes revealed hormone, stress, and development-related cis-elements. Gene ontology (GO) enrichment analysis showed that the CPR5 genes were largely related to biological regulation, developmental process, multicellular organismal process. Protein-protein interaction analysis predicted several trichome development related proteins (SIM, LGO, and GRL) directly interacting with CPR5 genes. Further, nine putative Gossypium-miRNAs were also identified, targeting Gossypium CPR5 genes. RNA-Seq data of G. arboreum (with trichomes) and G. herbaceum (with no trichomes) was used to perform the co-expression network analysis. GheCPR5.1 was identified as a hub gene in a co-expression network analysis. RT-qPCR of GheCPR5.1 gene in different tissues suggests that this gene has higher expressions in the petiole and might be a key candidate involved in the trichome development. Virus induced gene silencing of GheCPR5.1 (Ghe02G17590) confirms its role in trichome development and elongation. Current results provide proofs of the possible role of CPR5 genes and provide preliminary information for further studies of GheCPR5.1 functions in trichome development.

RevDate: 2022-06-23

Bao L, Ren J, Nguyen M, et al (2022)

The cellular function of ROP GTPase prenylation is important for multicellularity in the moss Physcomitrium patens.

Development (Cambridge, England), 149(12):.

A complete picture of how signaling pathways lead to multicellularity is largely unknown. Previously, we generated mutations in a protein prenylation enzyme, GGB, and showed that it is essential for maintaining multicellularity in the moss Physcomitrium patens. Here, we show that ROP GTPases act as downstream factors that are prenylated by GGB and themselves play an important role in the multicellularity of P. patens. We also show that the loss of multicellularity caused by the suppression of GGB or ROP GTPases is due to uncoordinated cell expansion, defects in cell wall integrity and the disturbance of the directional control of cell plate orientation. Expressing prenylatable ROP in the ggb mutant not only rescues multicellularity in protonemata but also results in development of gametophores. Although the prenylation of ROP is important for multicellularity, a higher threshold of active ROP is required for gametophore development. Thus, our results suggest that ROP activation via prenylation by GGB is a key process at both cell and tissue levels, facilitating the developmental transition from one dimension to two dimensions and to three dimensions in P. patens.

RevDate: 2022-06-21

Cameron-Pack ME, König SG, Reyes-Guevara A, et al (2022)

A personal cost of cheating can stabilize reproductive altruism during the early evolution of clonal multicellularity.

Biology letters, 18(6):20220059.

Understanding how cooperation evolved and is maintained remains an important and often controversial topic because cheaters that reap the benefits of cooperation without paying the costs can threaten the evolutionary stability of cooperative traits. Cooperation-and especially reproductive altruism-is particularly relevant to the evolution of multicellularity, as somatic cells give up their reproductive potential in order to contribute to the fitness of the newly emerged multicellular individual. Here, we investigated cheating in a simple multicellular species-the green alga Volvox carteri, in the context of the mechanisms that can stabilize reproductive altruism during the early evolution of clonal multicellularity. We found that the benefits cheater mutants can gain in terms of their own reproduction are pre-empted by a cost in survival due to increased sensitivity to stress. This personal cost of cheating reflects the antagonistic pleiotropic effects that the gene coding for reproductive altruism-regA-has at the cell level. Specifically, the expression of regA in somatic cells results in the suppression of their reproduction potential but also confers them with increased resistance to stress. Since regA evolved from a life-history trade-off gene, we suggest that co-opting trade-off genes into cooperative traits can provide a built-in safety system against cheaters in other clonal multicellular lineages.

RevDate: 2022-06-21

Kaufmann M, Schaupp AL, Sun R, et al (2022)

Identification of early neurodegenerative pathways in progressive multiple sclerosis.

Nature neuroscience [Epub ahead of print].

Progressive multiple sclerosis (MS) is characterized by unrelenting neurodegeneration, which causes cumulative disability and is refractory to current treatments. Drug development to prevent disease progression is an urgent clinical need yet is constrained by an incomplete understanding of its complex pathogenesis. Using spatial transcriptomics and proteomics on fresh-frozen human MS brain tissue, we identified multicellular mechanisms of progressive MS pathogenesis and traced their origin in relation to spatially distributed stages of neurodegeneration. By resolving ligand-receptor interactions in local microenvironments, we discovered defunct trophic and anti-inflammatory intercellular communications within areas of early neuronal decline. Proteins associated with neuronal damage in patient samples showed mechanistic concordance with published in vivo knockdown and central nervous system (CNS) disease models, supporting their causal role and value as potential therapeutic targets in progressive MS. Our findings provide a new framework for drug development strategies, rooted in an understanding of the complex cellular and signaling dynamics in human diseased tissue that facilitate this debilitating disease.

RevDate: 2022-06-20

Mori G, Delfino D, Pibiri P, et al (2022)

Origin and significance of the human DNase repertoire.

Scientific reports, 12(1):10364.

The human genome contains four DNase1 and two DNase2 genes. The origin and functional specialization of this repertoire are not fully understood. Here we use genomics and transcriptomics data to infer the evolutionary history of DNases and investigate their biological significance. Both DNase1 and DNase2 families have expanded in vertebrates since ~ 650 million years ago before the divergence of jawless and jawed vertebrates. DNase1, DNase1L1, and DNase1L3 co-existed in jawless fish, whereas DNase1L2 originated in amniotes by tandem duplication of DNase1. Among the non-human DNases, DNase1L4 and newly identified DNase1L5 derived from early duplications that were lost in terrestrial vertebrates. The ancestral gene of the DNase2 family, DNase2b, has been conserved in synteny with the Uox gene across 700 million years of animal evolution,while DNase2 originated in jawless fish. DNase1L1 acquired a GPI-anchor for plasma membrane attachment in bony fishes, and DNase1L3 acquired a C-terminal basic peptide for the degradation of microparticle DNA in jawed vertebrates. The appearance of DNase1L2, with a distinct low pH optimum and skin localization, is among the amniote adaptations to life on land. The expansion of the DNase repertoire in vertebrates meets the diversified demand for DNA debris removal in complex multicellular organisms.

RevDate: 2022-06-10

Barthlott W, Büdel B, Mail M, et al (2022)

Superhydrophobic Terrestrial Cyanobacteria and Land Plant Transition.

Frontiers in plant science, 13:880439.

Plants and other organisms have evolved structures and mechanisms for colonizing land since the Early Ordovician. In this context, their surfaces, the crucial physical interface with the environment, are mainly considered barriers against water loss. It is suggested that extreme water repellency (superhydrophobicity) was an additional key innovation for the transition of algae from water to land some 400 mya. Superhydrophobicity enhances gas exchange on land and excludes aquatic competitors in water films. In a different context, in material science and surface technology, superhydrophobicity has also become one of the most important bioinspired innovations enabling the avoidance of water films and contamination. Here, we present data for an extremely water-repellent cyanobacterial biofilm of the desiccation tolerant Hassallia byssoidea providing evidence for a much earlier prokaryotic Precambrian (ca. 1-2 bya) origin of superhydrophobicity and chemical heterogeneities associated with land transition. The multicellular cyanobacterium is functionally differentiated in a submerged basal hydrophilic absorbing portion like a "rhizoid" and an upright emersed superhydrophobic "phyllocauloid" filament for assimilation, nitrogen fixation, and splash dispersed diaspores. Additional data are provided for superhydrophobic surfaces in terrestrial green algae and in virtually all ancestral land plants (Bryophytes, ferns and allies, Amborella, Nelumbo), slime molds, and fungi. Rethinking of superhydrophobicity as an essential first step for life in terrestrial environments is suggested.

RevDate: 2022-06-10

Minelli A, A Valero-Gracia (2022)

Spatially and Temporally Distributed Complexity-A Refreshed Framework for the Study of GRN Evolution.

Cells, 11(11): pii:cells11111790.

Irrespective of the heuristic value of interpretations of developmental processes in terms of gene regulatory networks (GRNs), larger-angle views often suffer from: (i) an inadequate understanding of the relationship between genotype and phenotype; (ii) a predominantly zoocentric vision; and (iii) overconfidence in a putatively hierarchical organization of animal body plans. Here, we constructively criticize these assumptions. First, developmental biology is pervaded by adultocentrism, but development is not necessarily egg to adult. Second, during development, many unicells undergo transcriptomic profile transitions that are comparable to those recorded in pluricellular organisms; thus, their study should not be neglected from the GRN perspective. Third, the putatively hierarchical nature of the animal body is mirrored in the GRN logic, but in relating genotype to phenotype, independent assessments of the dynamics of the regulatory machinery and the animal's architecture are required, better served by a combinatorial than by a hierarchical approach. The trade-offs between spatial and temporal aspects of regulation, as well as their evolutionary consequences, are also discussed. Multicellularity may derive from a unicell's sequential phenotypes turned into different but coexisting, spatially arranged cell types. In turn, polyphenism may have been a crucial mechanism involved in the origin of complex life cycles.

RevDate: 2022-06-09

Northey JJ, VM Weaver (2022)

Mechanosensitive steroid hormone signaling and cell fate.

Endocrinology pii:6604697 [Epub ahead of print].

Mechanical forces collaborate across length scales to coordinate cell fate during development and the dynamic homeostasis of adult tissues. Similarly, steroid hormones interact with their nuclear and non-nuclear receptors to regulate diverse physiological processes necessary for the appropriate development and function of complex multicellular tissues. Aberrant steroid hormone action is associated with tumors originating in hormone-sensitive tissues and its disruption forms the basis of several therapeutic interventions. Prolonged perturbations to mechanical forces may further foster tumor initiation and the evolution of aggressive metastatic disease. Recent evidence suggests that steroid hormone and mechanical signaling intersect to direct cell fate during development and tumor progression. Potential mechanosensitive steroid hormone signaling pathways along with their molecular effectors will be discussed in this context.

RevDate: 2022-06-08

Day TC, Márquez-Zacarías P, Bravo P, et al (2022)

Varied solutions to multicellularity: The biophysical and evolutionary consequences of diverse intercellular bonds.

Biophysics reviews, 3(2):021305.

The diversity of multicellular organisms is, in large part, due to the fact that multicellularity has independently evolved many times. Nonetheless, multicellular organisms all share a universal biophysical trait: cells are attached to each other. All mechanisms of cellular attachment belong to one of two broad classes; intercellular bonds are either reformable or they are not. Both classes of multicellular assembly are common in nature, having independently evolved dozens of times. In this review, we detail these varied mechanisms as they exist in multicellular organisms. We also discuss the evolutionary implications of different intercellular attachment mechanisms on nascent multicellular organisms. The type of intercellular bond present during early steps in the transition to multicellularity constrains future evolutionary and biophysical dynamics for the lineage, affecting the origin of multicellular life cycles, cell-cell communication, cellular differentiation, and multicellular morphogenesis. The types of intercellular bonds used by multicellular organisms may thus result in some of the most impactful historical constraints on the evolution of multicellularity.

RevDate: 2022-06-07

Nawabi AK, Jinfang S, Abbasi R, et al (2022)

Segmentation of Drug-Treated Cell Image and Mitochondrial-Oxidative Stress Using Deep Convolutional Neural Network.

Oxidative medicine and cellular longevity, 2022:5641727.

Most multicellular organisms require apoptosis, or programmed cell death, to function properly and survive. On the other hand, morphological and biochemical characteristics of apoptosis have remained remarkably consistent throughout evolution. Apoptosis is thought to have at least three functionally distinct phases: induction, effector, and execution. Recent studies have revealed that reactive oxygen species (ROS) and the oxidative stress could play an essential role in apoptosis. Advanced microscopic imaging techniques allow biologists to acquire an extensive amount of cell images within a matter of minutes which rule out the manual analysis of image data acquisition. The segmentation of cell images is often considered the cornerstone and central problem for image analysis. Currently, the issue of segmentation of mitochondrial cell images via deep learning receives increasing attention. The manual labeling of cell images is time-consuming and challenging to train a pro. As a courtesy method, mitochondrial cell imaging (MCI) is proposed to identify the normal, drug-treated, and diseased cells. Furthermore, cell movement (fission and fusion) is measured to evaluate disease risk. The newly proposed drug-treated, normal, and diseased image segmentation (DNDIS) algorithm can quickly segment mitochondrial cell images without supervision and further segment the highly drug-treated cells in the picture, i.e., normal, diseased, and drug-treated cells. The proposed method is based on the ResNet-50 deep learning algorithm. The dataset consists of 414 images mainly categorised into different sets (drug, diseased, and normal) used microscopically. The proposed automated segmentation method has outperformed and secured high precision (90%, 92%, and 94%); moreover, it also achieves proper training. This study will benefit medicines and diseased cell measurements in medical tests and clinical practices.

RevDate: 2022-06-07

Abumsimir B, Al-Qaisi TS, Y Kasmi (2022)

Rereading the genetic origin of cancer: the puzzle of all eras.

Future science OA, 8(5):FSO799.

RevDate: 2022-06-07

Phillips JE, Santos M, Konchwala M, et al (2022)

Genome editing in the unicellular holozoan Capsaspora owczarzaki suggests a premetazoan role for the Hippo pathway in multicellular morphogenesis.

eLife, 11: pii:77598.

Animal development is mediated by a surprisingly small set of canonical signaling pathways such as Wnt, Hedgehog, TGF-beta, Notch, and Hippo pathways. Although once thought to be present only in animals, recent genome sequencing has revealed components of these pathways in the closest unicellular relatives of animals. These findings raise questions about the ancestral functions of these developmental pathways and their potential role in the emergence of animal multicellularity. Here, we provide the first functional characterization of any of these developmental pathways in unicellular organisms by developing techniques for genetic manipulation in Capsaspora owczarzaki, a close unicellular relative of animals that displays aggregative multicellularity. We then use these tools to characterize the Capsaspora ortholog of the Hippo signaling nuclear effector YAP/TAZ/Yorkie (coYki), a key regulator of tissue size in animals. In contrast to what might be expected based on studies in animals, we show that coYki is dispensable for cell proliferation but regulates cytoskeletal dynamics and the three-dimensional (3D) shape of multicellular structures. We further demonstrate that the cytoskeletal abnormalities of individual coYki mutant cells underlie the abnormal 3D shape of coYki mutant aggregates. Taken together, these findings implicate an ancestral role for the Hippo pathway in cytoskeletal dynamics and multicellular morphogenesis predating the origin of animal multicellularity, which was co-opted during evolution to regulate cell proliferation.

RevDate: 2022-06-07

Bentley MA, Yates CA, Hein J, et al (2022)

Pleiotropic constraints promote the evolution of cooperation in cellular groups.

PLoS biology, 20(6):e3001626 pii:PBIOLOGY-D-21-01691.

The evolution of cooperation in cellular groups is threatened by lineages of cheaters that proliferate at the expense of the group. These cell lineages occur within microbial communities, and multicellular organisms in the form of tumours and cancer. In contrast to an earlier study, here we show how the evolution of pleiotropic genetic architectures-which link the expression of cooperative and private traits-can protect against cheater lineages and allow cooperation to evolve. We develop an age-structured model of cellular groups and show that cooperation breaks down more slowly within groups that tie expression to a private trait than in groups that do not. We then show that this results in group selection for pleiotropy, which strongly promotes cooperation by limiting the emergence of cheater lineages. These results predict that pleiotropy will rapidly evolve, so long as groups persist long enough for cheater lineages to threaten cooperation. Our results hold when pleiotropic links can be undermined by mutations, when pleiotropy is itself costly, and in mixed-genotype groups such as those that occur in microbes. Finally, we consider features of multicellular organisms-a germ line and delayed reproductive maturity-and show that pleiotropy is again predicted to be important for maintaining cooperation. The study of cancer in multicellular organisms provides the best evidence for pleiotropic constraints, where abberant cell proliferation is linked to apoptosis, senescence, and terminal differentiation. Alongside development from a single cell, we propose that the evolution of pleiotropic constraints has been critical for cooperation in many cellular groups.

RevDate: 2022-06-03
CmpDate: 2022-06-03

Udayantha HMV, Samaraweera AV, Liyanage DS, et al (2022)

Molecular characterization, antiviral activity, and UV-B damage responses of Caspase-9 from Amphiprion clarkii.

Fish & shellfish immunology, 125:247-257.

Apoptosis plays a vital role in maintaining cellular homeostasis in multicellular organisms. Caspase-9 (casp-9) is one of the major initiator caspases that induces apoptosis by activating downstream intrinsic apoptosis pathway genes. Here, we isolated the cDNA sequence (1992 bp) of caspase-9 from Amphiprion clarkii (Accasp-9) that consists of a 1305 bp coding region and encodes a 434 aa protein. In silico analysis showed that Accasp-9 has a theoretical isoelectric point of 5.81 and a molecular weight of 48.45 kDa. Multiple sequence alignment revealed that the CARD domain is located at the N-terminus, whereas the large P-20 and small P-10 domains are located at the C-terminus. Moreover, a highly conserved pentapeptide active site (296QACGG301), as well as histidine and cysteine active sites, are also retained at the C-terminus. In phylogenetic analysis, Accasp-9 formed a clade with casp-9 from different species, distinct from other caspases. Accasp-9 was highly expressed in the gill and intestine compared with other tissues analyzed in healthy A. clarkii. Accasp-9 expression was significantly elevated in the blood after stimulation with Vibrio harveyi and polyinosinic:polycytidylic acid (poly I:C; 12-48 h), but not with lipopolysaccharide. The nucleoprotein expression of the viral hemorrhagic septicemia virus was significantly reduced in Accasp-9 overexpressed fathead minnow (FHM) cells compared with that in the control. In addition, other in vitro assays revealed that cell apoptosis was significantly elevated in poly I:C and UV-B-treated Accasp-9 transfected FHM cells. However, H248P or C298S mutated Accasp-9 significantly reduced apoptosis in UV-B irradiated cells. Collectively, our results show that Accasp-9 might play a defensive role against invading pathogens and UV-B radiation and H248 and C298 active residues are significantly involved in apoptosis in teleosts.

RevDate: 2022-06-03
CmpDate: 2022-06-03

Wang B, Zhu F, Shi Z, et al (2022)

Molecular characteristics, polymorphism and expression analysis of mhc Ⅱ in yellow catfish(pelteobagrus fulvidraco)responding to Flavobacterium columnare infection.

Fish & shellfish immunology, 125:90-100.

The major histocompatibility complex (MHC) is an important component of the immune system of vertebrates, which plays a vital role in presenting extrinsic antigens. In this study, we cloned and characterized the mhc ⅡA and mhc ⅡB genes of yellow catfish Pelteobagrus fulvidraco. The open reading frames (ORFs) of mhc ⅡA and mhc ⅡB genes were 708 bp and 747bp in length, encoding 235 and 248 amino acids, respectively. The structure of mhc ⅡA and mhc ⅡB includes a signal peptide, an α1/β1 domain, an α2/β2 domain, a transmembrane region and a cytoplasmic region. Homologous identity analysis revealed that both mhc ⅡA and mhc ⅡB shared high protein sequence similarity with that of Chinese longsnout catfish Leiocassis longirostris. mhc ⅡA and mhc ⅡB showed similar expression patterns in different tissues, with the higher expression level in spleen, head kidney and gill and lower expression in liver, stomach, gall bladder and heart. The mRNA expression level of mhc ⅡA and mhc ⅡB in different embryonic development stages also showed the similar trends. The higher expression was detected from fertilized egg to 32 cell stage, low expression from multicellular period to 3 days post hatching (dph), and then the expression increased to a higher level from 4 dph to 14 dph. The mRNA expression levels of mhc ⅡA and mhc ⅡB were significantly up-regulated not only in the body kidney and spleen, but also in the midgut, hindgut, liver and gill after challenge of Flavobacterium columnare. The results suggest that Mhc Ⅱ plays an important role in the anti-infection process of yellow catfish P. fulvidraco.

RevDate: 2022-06-02

Díaz E, Febres A, Giammarresi M, et al (2022)

G Protein-Coupled Receptors as Potential Intercellular Communication Mediators in Trypanosomatidae.

Frontiers in cellular and infection microbiology, 12:812848.

Detection and transduction of environmental signals, constitute a prerequisite for successful parasite invasion; i.e., Leishmania transmission, survival, pathogenesis and disease manifestation and dissemination, with diverse molecules functioning as inter-cellular signaling ligands. Receptors [i.e., G protein-coupled receptors (GPCRs)] and their associated transduction mechanisms, well conserved through evolution, specialize in this function. However, canonical GPCR-related signal transduction systems have not been described in Leishmania, although orthologs, with reduced domains and function, have been identified in Trypanosomatidae. These inter-cellular communication means seem to be essential for multicellular and unicellular organism's survival. GPCRs are flexible in their molecular architecture and may interact with the so-called receptor activity-modifying proteins (RAMPs), which modulate their function, changing GPCRs pharmacology, acting as chaperones and regulating signaling and/or trafficking in a receptor-dependent manner. In the skin, vasoactive- and neuro- peptides released in response to the noxious stimuli represented by the insect bite may trigger parasite physiological responses, for example, chemotaxis. For instance, in Leishmania (V.) braziliensis, sensory [Substance P, SP, chemoattractant] and autonomic [Vasoactive Intestinal Peptide, VIP, and Neuropeptide Y, NPY, chemorepellent] neuropeptides at physiological levels stimulate in vitro effects on parasite taxis. VIP and NPY chemotactic effects are impaired by their corresponding receptor antagonists, suggesting that the stimulated responses might be mediated by putative GPCRs (with essential conserved receptor domains); the effect of SP is blocked by [(D-Pro 2, D-Trp7,9]-Substance P (10-6 M)] suggesting that it might be mediated by neurokinin-1 transmembrane receptors. Additionally, vasoactive molecules like Calcitonin Gene-Related Peptide [CGRP] and Adrenomedullin [AM], exert a chemorepellent effect and increase the expression of a 24 kDa band recognized in western blot analysis by (human-)-RAMP-2 antibodies. In-silico search oriented towards GPCRs-like receptors and signaling cascades detected a RAMP-2-aligned sequence corresponding to Leishmania folylpolyglutamate synthase and a RAMP-3 aligned protein, a hypothetical Leishmania protein with yet unknown function, suggesting that in Leishmania, CGRP and AM activities may be modulated by RAMP- (-2) and (-3) homologs. The possible presence of proteins and molecules potentially involved in GPCRs cascades, i.e., RAMPs, signpost conservation of ancient signaling systems associated with responses, fundamental for cell survival, (i.e., taxis and migration) and may constitute an open field for description of pharmacophores against Leishmania parasites.

RevDate: 2022-06-01

Goswami P, He K, Li J, et al (2022)

Magnetotactic bacteria and magnetofossils: ecology, evolution and environmental implications.

NPJ biofilms and microbiomes, 8(1):43.

Magnetotactic bacteria (MTB) are a group of phylogenetically diverse and morphologically varied microorganisms with a magnetoresponsive capability called magnetotaxis or microbial magnetoreception. MTB are a distinctive constituent of the microbiome of aquatic ecosystems because they use Earth's magnetic field to align themselves in a north or south facing direction and efficiently navigate to their favored microenvironments. They have been identified worldwide from diverse aquatic and waterlogged microbiomes, including freshwater, saline, brackish and marine ecosystems, and some extreme environments. MTB play important roles in the biogeochemical cycling of iron, sulphur, phosphorus, carbon and nitrogen in nature and have been recognized from in vitro cultures to sequester heavy metals like selenium, cadmium, and tellurium, which makes them prospective candidate organisms for aquatic pollution bioremediation. The role of MTB in environmental systems is not limited to their lifespan; after death, fossil magnetosomal magnetic nanoparticles (known as magnetofossils) are a promising proxy for recording paleoenvironmental change and geomagnetic field history. Here, we summarize the ecology, evolution, and environmental function of MTB and the paleoenvironmental implications of magnetofossils in light of recent discoveries.

RevDate: 2022-06-01

Bonforti A, R Solé (2022)

Unicellular-multicellular evolutionary branching driven by resource limitations.

Journal of the Royal Society, Interface, 19(191):20220018.

Multicellular life forms have evolved many times on our planet, suggesting that this is a common evolutionary innovation. Multiple advantages have been proposed for the emergence of multicellularity (MC). In this paper, we address the problem of how the first precondition for MC, namely 'stay together', might have occurred under spatially limited resources exploited by a population of unicellular agents. Using a minimal model of evolved cell-cell adhesion among growing and dividing cells that exploit a localized resource with a given size, we show that a transition occurs at a critical resource size separating a phase of evolved multicellular aggregates from a phase where unicellularity (UC) is favoured. The two phases are separated by an intermediate domain where both UC and MC can be selected by evolution. This model provides a minimal approach to the early stages that were required to transition from individuality to cohesive groups of cells associated with a physical cooperative effect: when resources are present only in a localized portion of the habitat, MC is a desirable property as it helps cells to keep close to the available local nutrients.

RevDate: 2022-05-31
CmpDate: 2022-05-03

Staps M, CE Tarnita (2022)

When being flexible matters: Ecological underpinnings for the evolution of collective flexibility and task allocation.

Proceedings of the National Academy of Sciences of the United States of America, 119(18):e2116066119.

Task allocation is a central feature of collective organization. Living collective systems, such as multicellular organisms or social insect colonies, have evolved diverse ways to allocate individuals to different tasks, ranging from rigid, inflexible task allocation that is not adjusted to changing circumstances to more fluid, flexible task allocation that is rapidly adjusted to the external environment. While the mechanisms underlying task allocation have been intensely studied, it remains poorly understood whether differences in the flexibility of task allocation can be viewed as adaptive responses to different ecological contexts—for example, different degrees of temporal variability. Motivated by this question, we develop an analytically tractable mathematical framework to explore the evolution of task allocation in dynamic environments. We find that collective flexibility is not necessarily always adaptive, and fails to evolve in environments that change too slowly (relative to how long tasks can be left unattended) or too quickly (relative to how rapidly task allocation can be adjusted). We further employ the framework to investigate how environmental variability impacts the internal organization of task allocation, which allows us to propose adaptive explanations for some puzzling empirical observations, such as seemingly unnecessary task switching under constant environmental conditions, apparent task specialization without efficiency benefits, and high levels of individual inactivity. Altogether, this work provides a general framework for probing the evolved diversity of task allocation strategies in nature and reinforces the idea that considering a system’s ecology is crucial to explaining its collective organization.

RevDate: 2022-05-28

Cui K, Pan H, Chen J, et al (2022)

A Novel Isolate of Spherical Multicellular Magnetotactic Prokaryotes Has Two Magnetosome Gene Clusters and Synthesizes Both Magnetite and Greigite Crystals.

Microorganisms, 10(5): pii:microorganisms10050925.

Multicellular magnetotactic prokaryotes (MMPs) are a unique group of magnetotactic bacteria that are composed of 10-100 individual cells and show coordinated swimming along magnetic field lines. MMPs produce nanometer-sized magnetite (Fe3O4) and/or greigite (Fe3S4) crystals-termed magnetosomes. Two types of magnetosome gene cluster (MGC) that regulate biomineralization of magnetite and greigite have been found. Here, we describe a dominant spherical MMP (sMMP) species collected from the intertidal sediments of Jinsha Bay, in the South China Sea. The sMMPs were 4.78 ± 0.67 μm in diameter, comprised 14-40 cells helical symmetrically, and contained bullet-shaped magnetite and irregularly shaped greigite magnetosomes. Two sets of MGCs, one putatively related to magnetite biomineralization and the other to greigite biomineralization, were identified in the genome of the sMMP, and two sets of paralogous proteins (Mam and Mad) that may function separately and independently in magnetosome biomineralization were found. Phylogenetic analysis indicated that the sMMPs were affiliated with Deltaproteobacteria. This is the first direct report of two types of magnetosomes and two sets of MGCs being detected in the same sMMP. The study provides new insights into the mechanism of biomineralization of magnetosomes in MMPs, and the evolutionary origin of MGCs.

RevDate: 2022-05-28

Paradžik T, Podgorski II, Vojvoda Zeljko T, et al (2022)

Ancient Origins of Cytoskeletal Crosstalk: Spectraplakin-like Proteins Precede the Emergence of Cortical Microtubule Stabilization Complexes as Crosslinkers.

International journal of molecular sciences, 23(10): pii:ijms23105594.

Adhesion between cells and the extracellular matrix (ECM) is one of the prerequisites for multicellularity, motility, and tissue specialization. Focal adhesions (FAs) are defined as protein complexes that mediate signals from the ECM to major components of the cytoskeleton (microtubules, actin, and intermediate filaments), and their mutual communication determines a variety of cellular processes. In this study, human cytoskeletal crosstalk proteins were identified by comparing datasets with experimentally determined cytoskeletal proteins. The spectraplakin dystonin was the only protein found in all datasets. Other proteins (FAK, RAC1, septin 9, MISP, and ezrin) were detected at the intersections of FAs, microtubules, and actin cytoskeleton. Homology searches for human crosstalk proteins as queries were performed against a predefined dataset of proteomes. This analysis highlighted the importance of FA communication with the actin and microtubule cytoskeleton, as these crosstalk proteins exhibit the highest degree of evolutionary conservation. Finally, phylogenetic analyses elucidated the early evolutionary history of spectraplakins and cortical microtubule stabilization complexes (CMSCs) as model representatives of the human cytoskeletal crosstalk. While spectraplakins probably arose at the onset of opisthokont evolution, the crosstalk between FAs and microtubules is associated with the emergence of metazoans. The multiprotein complexes contributing to cytoskeletal crosstalk in animals gradually gained in complexity from the onset of metazoan evolution.

RevDate: 2022-05-28

Paul B, Sterner ZR, Buchholz DR, et al (2022)

Thyroid and Corticosteroid Signaling in Amphibian Metamorphosis.

Cells, 11(10): pii:cells11101595.

In multicellular organisms, development is based in part on the integration of communication systems. Two neuroendocrine axes, the hypothalamic-pituitary-thyroid and the hypothalamic-pituitary-adrenal/interrenal axes, are central players in orchestrating body morphogenesis. In all vertebrates, the hypothalamic-pituitary-thyroid axis controls thyroid hormone production and release, whereas the hypothalamic-pituitary-adrenal/interrenal axis regulates the production and release of corticosteroids. One of the most salient effects of thyroid hormones and corticosteroids in post-embryonic developmental processes is their critical role in metamorphosis in anuran amphibians. Metamorphosis involves modifications to the morphological and biochemical characteristics of all larval tissues to enable the transition from one life stage to the next life stage that coincides with an ecological niche switch. This transition in amphibians is an example of a widespread phenomenon among vertebrates, where thyroid hormones and corticosteroids coordinate a post-embryonic developmental transition. The review addresses the functions and interactions of thyroid hormone and corticosteroid signaling in amphibian development (metamorphosis) as well as the developmental roles of these two pathways in vertebrate evolution.

RevDate: 2022-05-27

Puzakov MV, LV Puzakova (2022)

[Prevalence, Diversity, and Evolution of L18 (DD37E) Transposons in the Genomes of Cnidarians].

Molekuliarnaia biologiia, 56(3):476-490.

Transposable elements have a significant impact on the structure and functioning of multicellular genomes, and also serve as a source of new genes. Studying the diversity and evolution of transposable elements in different taxa is necessary for the fundamental understanding of their role in genomes. The Tc1/mariner elements are one of the most widespread and diverse groups of DNA transposons. In this work, the structure, distribution, diversity, and evolution of the L18 (DD37E) elements in the genomes of cnidarians (Cnidaria) were studied for the first time. As a result, it was found that the L18 group is an independent family (and not a subfamily of the TLE family, as previously thought) in the Tc1/mariner superfamily. Of the 51 detected elements, only four had potentially functional copies. It is assumed that the L18 transposons are of ancient origin, and, in addition, the elements found in the genomes of organisms of the Anthozoa and Hydrozoa classes do not come from a common ancestral transposon within the Cnidaria phylum. In organisms of the Hydrozoa class, L18 transposons appeared as a result of horizontal transfer at a later time period. An intraspecies comparison of the diversity of the L18 elements demonstrates high homogeneity with respect to "old" transposons, which have already lost their activity. At the same time, distant populations, as in the case of Hydra viridissima, have differences in the representation of DNA transposons and the number of copies. These data supplement the knowledge on the diversity and evolution of Tc1/mariner transposons and contribute to the study of the influence of mobile genetic elements on the evolution of multicellular organisms.

RevDate: 2022-05-27
CmpDate: 2022-05-27

Verdan M, Resende E, Cypriano J, et al (2022)

Occurrence of south- and north-seeking multicellular magnetotactic prokaryotes in a coastal lagoon in the South Hemisphere.

International microbiology : the official journal of the Spanish Society for Microbiology, 25(2):309-323.

Magnetotactic bacteria (MTB) response to the magnetic field can be classified into north-seeking (NS) and south-seeking (SS), which usually depends on their inhabiting site in the North and South Hemisphere, respectively. However, uncommon inverted polarity was observed on both hemispheres. Here, we studied magnetotactic multicellular prokaryotes (MMPs) from a coastal lagoon in Brazil collected in April and August 2014. MMPs from the first sampling period presented both magnetotactic behaviors, while MMPs collected in August/2014 were only SS. Phylogenetic analysis based on the 16S rRNA coding gene showed that these organisms belong to the Deltaproteobacteria class. The 16S rRNA gene sequences varied among MMPs regardless of the sampling period, and similarity values were not related to the type of magnetotactic response presented by the microorganisms. Therefore, differences in the magnetotactic behavior might result from the physiological state of MMPs, the availability of resources, or the instability of the chemical gradient in the environment. This is the first report of NS magnetotactic behavior on MMPs from the South Hemisphere.

RevDate: 2022-05-23

Bush JO (2022)

Cellular and molecular mechanisms of EPH/EPHRIN signaling in evolution and development.

Current topics in developmental biology, 149:153-201.

The EPH receptor tyrosine kinases and their signaling partners, the EPHRINS, comprise a large class of cell signaling molecules that plays diverse roles in development. As cell membrane-anchored signaling molecules, they regulate cellular organization by modulating the strength of cellular contacts, usually by impacting the actin cytoskeleton or cell adhesion programs. Through these cellular functions, EPH/EPHRIN signaling often regulates tissue shape. Indeed, recent evidence indicates that this signaling family is ancient and associated with the origin of multicellularity. Though extensively studied, our understanding of the signaling mechanisms employed by this large family of signaling proteins remains patchwork, and a truly "canonical" EPH/EPHRIN signal transduction pathway is not known and may not exist. Instead, several foundational evolutionarily conserved mechanisms are overlaid by a myriad of tissue -specific functions, though common themes emerge from these as well. Here, I review recent advances and the related contexts that have provided new understanding of the conserved and varied molecular and cellular mechanisms employed by EPH/EPHRIN signaling during development.

RevDate: 2022-05-16

Ritch SJ, CM Telleria (2022)

The Transcoelomic Ecosystem and Epithelial Ovarian Cancer Dissemination.

Frontiers in endocrinology, 13:886533.

Epithelial ovarian cancer (EOC) is considered the deadliest gynecological disease and is normally diagnosed at late stages, at which point metastasis has already occurred. Throughout disease progression, EOC will encounter various ecosystems and the communication between cancer cells and these microenvironments will promote the survival and dissemination of EOC. The primary tumor is thought to develop within the ovaries or the fallopian tubes, both of which provide a microenvironment with high risk of causing DNA damage and enhanced proliferation. EOC disseminates by direct extension from the primary tumors, as single cells or multicellular aggregates. Under the influence of cellular and non-cellular factors, EOC spheroids use the natural flow of peritoneal fluid to reach distant organs within the peritoneal cavity. These cells can then implant and seed distant organs or tissues, which develop rapidly into secondary tumor nodules. The peritoneal tissue and the omentum are two common sites of EOC metastasis, providing a microenvironment that supports EOC invasion and survival. Current treatment for EOC involves debulking surgery followed by platinum-taxane combination chemotherapy; however, most patients will relapse with a chemoresistant disease with tumors developed within the peritoneum. Therefore, understanding the role of the unique microenvironments that promote EOC transcoelomic dissemination is important in improving patient outcomes from this disease. In this review article, we address the process of ovarian cancer cellular fate at the site of its origin in the secretory cells of the fallopian tube or in the ovarian surface epithelial cells, their detachment process, how the cells survive in the peritoneal fluid avoiding cell death triggers, and how cancer- associated cells help them in the process. Finally, we report the mechanisms used by the ovarian cancer cells to adhere and migrate through the mesothelial monolayer lining the peritoneum. We also discuss the involvement of the transcoelomic ecosystem on the development of chemoresistance of EOC.

RevDate: 2022-05-16

Zhang J, Shen N, Li C, et al (2022)

Population genomics provides insights into the genetic basis of adaptive evolution in the mushroom-forming fungus Lentinula edodes.

Journal of advanced research, 38:91-106 pii:S2090-1232(21)00189-2.

Introduction: Mushroom-forming fungi comprise diverse species that develop complex multicellular structures. In cultivated species, both ecological adaptation and artificial selection have driven genome evolution. However, little is known about the connections among genotype, phenotype and adaptation in mushroom-forming fungi.

Objectives: This study aimed to (1) uncover the population structure and demographic history of Lentinula edodes, (2) dissect the genetic basis of adaptive evolution in L. edodes, and (3) determine if genes related to fruiting body development are involved in adaptive evolution.

Methods: We analyzed genomes and fruiting body-related traits (FBRTs) in 133 L. edodes strains and conducted RNA-seq analysis of fruiting body development in the YS69 strain. Combined methods of genomic scan for divergence, genome-wide association studies (GWAS), and RNA-seq were used to dissect the genetic basis of adaptive evolution.

Results: We detected three distinct subgroups of L. edodes via single nucleotide polymorphisms, which showed robust phenotypic and temperature response differentiation and correlation with geographical distribution. Demographic history inference suggests that the subgroups diverged 36,871 generations ago. Moreover, L. edodes cultivars in China may have originated from the vicinity of Northeast China. A total of 942 genes were found to be related to genetic divergence by genomic scan, and 719 genes were identified to be candidates underlying FBRTs by GWAS. Integrating results of genomic scan and GWAS, 80 genes were detected to be related to phenotypic differentiation. A total of 364 genes related to fruiting body development were involved in genetic divergence and phenotypic differentiation.

Conclusion: Adaptation to the local environment, especially temperature, triggered genetic divergence and phenotypic differentiation of L. edodes. A general model for genetic divergence and phenotypic differentiation during adaptive evolution in L. edodes, which involves in signal perception and transduction, transcriptional regulation, and fruiting body morphogenesis, was also integrated here.

RevDate: 2022-05-16

Heinz MC, Peters NA, Oost KC, et al (2022)

Liver Colonization by Colorectal Cancer Metastases Requires YAP-Controlled Plasticity at the Micrometastatic Stage.

Cancer research, 82(10):1953-1968.

Micrometastases of colorectal cancer can remain dormant for years prior to the formation of actively growing, clinically detectable lesions (i.e., colonization). A better understanding of this step in the metastatic cascade could help improve metastasis prevention and treatment. Here we analyzed liver specimens of patients with colorectal cancer and monitored real-time metastasis formation in mouse livers using intravital microscopy to reveal that micrometastatic lesions are devoid of cancer stem cells (CSC). However, lesions that grow into overt metastases demonstrated appearance of de novo CSCs through cellular plasticity at a multicellular stage. Clonal outgrowth of patient-derived colorectal cancer organoids phenocopied the cellular and transcriptomic changes observed during in vivo metastasis formation. First, formation of mature CSCs occurred at a multicellular stage and promoted growth. Conversely, failure of immature CSCs to generate more differentiated cells arrested growth, implying that cellular heterogeneity is required for continuous growth. Second, early-stage YAP activity was required for the survival of organoid-forming cells. However, subsequent attenuation of early-stage YAP activity was essential to allow for the formation of cell type heterogeneity, while persistent YAP signaling locked micro-organoids in a cellularly homogenous and growth-stalled state. Analysis of metastasis formation in mouse livers using single-cell RNA sequencing confirmed the transient presence of early-stage YAP activity, followed by emergence of CSC and non-CSC phenotypes, irrespective of the initial phenotype of the metastatic cell of origin. Thus, establishment of cellular heterogeneity after an initial YAP-controlled outgrowth phase marks the transition to continuously growing macrometastases.

SIGNIFICANCE: Characterization of the cell type dynamics, composition, and transcriptome of early colorectal cancer liver metastases reveals that failure to establish cellular heterogeneity through YAP-controlled epithelial self-organization prohibits the outgrowth of micrometastases. See related commentary by LeBleu, p. 1870.

RevDate: 2022-05-16
CmpDate: 2022-04-20

Pichugin Y, A Traulsen (2022)

The possible modes of microbial reproduction are fundamentally restricted by distribution of mass between parent and offspring.

Proceedings of the National Academy of Sciences of the United States of America, 119(12):e2122197119.

Multiple modes of asexual reproduction are observed among microbial organisms in natural populations. These modes are not only subject to evolution, but may drive evolutionary competition directly through their impact on population growth rates. The most prominent transition between two such modes is the one from unicellularity to multicellularity. We present a model of the evolution of reproduction modes, where a parent organism fragments into smaller parts. While the size of an organism at fragmentation, the number of offspring, and their sizes may vary a lot, the combined mass of fragments is limited by the mass of the parent organism. We found that mass conservation can fundamentally limit the number of possible reproduction modes. This has important direct implications for microbial life: For unicellular species, the interplay between cell shape and kinetics of the cell growth implies that the largest and the smallest possible cells should be rod shaped rather than spherical. For primitive multicellular species, these considerations can explain why rosette cell colonies evolved a mechanistically complex binary split reproduction. Finally, we show that the loss of organism mass during sporulation can explain the macroscopic sizes of the formally unicellular microorganism Myxomycetes plasmodium. Our findings demonstrate that a number of seemingly unconnected phenomena observed in unrelated species may be different manifestations of the same underlying process.

RevDate: 2022-05-14

Stange K, Keric A, Friese A, et al (2022)

Preparation of Spheroids from Primary Pig Cells in a Mid-Scale Bioreactor Retaining Their Myogenic Potential.

Cells, 11(9): pii:cells11091453.

Three-dimensional cell culture techniques mimic the in vivo cell environment more adequately than flat surfaces. Spheroids are multicellular aggregates and we aimed to produce scaffold-free spheroids of myogenic origin, called myospheres, using a mid-scale incubator and bioreactor hybrid. For the first time, we obtained spheroids from primary porcine muscle cells (PMCs) with this technology and compared their morphology and growth parameters, marker expression, and myogenic potential to C2C12-derived spheroids. Both cell types were able to form round-shaped spheroids in the bioreactor already after 24 h. The mean diameter of the C2C12 spheroids (44.6 µm) was larger than that of the PMCs (32.7 µm), and the maximum diameter exceeded 1 mm. C2C12 cells formed less aggregates than PMCs with a higher packing density (cell nuclei/mm2). After dissociation from the spheroids, C2C12 cells and PMCs started to proliferate again and were able to differentiate into the myogenic lineage, as shown by myotube formation and the expression of F-Actin, Desmin, MyoG, and Myosin. For C2C12, multinucleated syncytia and Myosin expression were observed in spheroids, pointing to accelerated myogenic differentiation. In conclusion, the mid-scale incubator and bioreactor system is suitable for spheroid formation and cultivation from primary muscle cells while preserving their myogenic potential.

RevDate: 2022-05-13

Eskandari E, CJ Eaves (2022)

Paradoxical roles of caspase-3 in regulating cell survival, proliferation, and tumorigenesis.

The Journal of cell biology, 221(6):.

Caspase-3 is a widely expressed member of a conserved family of proteins, generally recognized for their activated proteolytic roles in the execution of apoptosis in cells responding to specific extrinsic or intrinsic inducers of this mode of cell death. However, accumulating evidence indicates that caspase-3 also plays key roles in regulating the growth and homeostatic maintenance of both normal and malignant cells and tissues in multicellular organisms. Given that yeast possess an ancestral caspase-like gene suggests that the caspase-3 protein may have acquired different functions later during evolution to better meet the needs of more complex multicellular organisms, but without necessarily losing all of the functions of its ancestral yeast precursor. This review provides an update on what has been learned about these interesting dichotomous roles of caspase-3, their evolution, and their potential relevance to malignant as well as normal cell biology.

RevDate: 2022-05-12
CmpDate: 2022-05-12

Toret C, Picco A, Boiero-Sanders M, et al (2022)

The cellular slime mold Fonticula alba forms a dynamic, multicellular collective while feeding on bacteria.

Current biology : CB, 32(9):1961-1973.e4.

Multicellularity evolved in fungi and animals, or the opisthokonts, from their common amoeboflagellate ancestor but resulted in strikingly distinct cellular organizations. The origins of this multicellularity divergence are not known. The stark mechanistic differences that underlie the two groups and the lack of information about ancestral cellular organizations limits progress in this field. We discovered a new type of invasive multicellular behavior in Fonticula alba, a unique species in the opisthokont tree, which has a simple, bacteria-feeding sorocarpic amoeba lifestyle. This invasive multicellularity follows germination dependent on the bacterial culture state, after which amoebae coalesce to form dynamic collectives that invade virgin bacterial resources. This bacteria-dependent social behavior emerges from amoeba density and allows for rapid and directed invasion. The motile collectives have animal-like properties but also hyphal-like search and invasive behavior. These surprising findings enrich the diverse multicellularities present within the opisthokont lineage and offer a new perspective on fungal origins.

RevDate: 2022-05-11

Lee DW, Kang J, Hwang HJ, et al (2018)

Pitch-tunable pillar arrays for high-throughput culture and immunohistological analysis of tumor spheroids.

RSC advances, 8(9):4494-4502 pii:c7ra09090k.

Tumor spheroids are multicellular, three-dimensional (3D) cell culture models closely mimicking the microenvironments of human tumors in vivo, thereby providing enhanced predictability, clinical relevancy of drug efficacy and the mechanism of action. Conventional confocal microscopic imaging remains inappropriate for immunohistological analysis due to current technical limits in immunostaining using antibodies and imaging cells grown in 3D multicellular contexts. Preparation of microsections of these spheroids represents a best alternative, yet their sub-millimeter size and fragility make it less practical for high-throughput screening. To address these problems, we developed a pitch-tunable 5 × 5 mini-pillar array chip for culturing and sectioning tumor spheroids in a high throughput manner. Tumor spheroids were 3D cultured in an alginate matrix using a twenty-five mini-pillar array which aligns to a 96-well. At least a few tens of spheroids per pillar were cultured and as many as 25 different treatment conditions per chip were evaluated, which indicated the high throughput manner of the 5 × 5 pillar array chip. The twenty-five mini-pillars were then rearranged to a transferring pitch so that spheroid-containing gel caps from all pillars can be embedded into a specimen block. Tissue array sections were then prepared and stained for immunohistological examination. The utility of this pitch-tunable pillar array was demonstrated by evaluating drug distribution and expression levels of several proteins following drug treatment in 3D tumor spheroids. Overall, our mini-pillar array provides a novel platform that can be useful for culturing tumor spheroids as well as for immunohistological analysis in a multiplexed and high throughput manner.

RevDate: 2022-05-09

de la Fuente M, M Novo (2022)

Understanding Diversity, Evolution, and Structure of Small Heat Shock Proteins in Annelida Through in Silico Analyses.

Frontiers in physiology, 13:817272 pii:817272.

Small heat shock proteins (sHsps) are oligomeric stress proteins characterized by an α-crystallin domain (ACD). These proteins are localized in different subcellular compartments and play critical roles in the stress physiology of tissues, organs, and whole multicellular eukaryotes. They are ubiquitous proteins found in all living organisms, from bacteria to mammals, but they have never been studied in annelids. Here, a data set of 23 species spanning the annelid tree of life, including mostly transcriptomes but also two genomes, was interrogated and 228 novel putative sHsps were identified and manually curated. The analysis revealed very high protein diversity and showed that a significant number of sHsps have a particular dimeric architecture consisting of two tandemly repeated ACDs. The phylogenetic analysis distinguished three main clusters, two of them containing both monomeric sHsps, and ACDs located downstream in the dimeric sHsps, and the other one comprising the upstream ACDs from those dimeric forms. Our results support an evolutionary history of these proteins based on duplication events prior to the Spiralia split. Monomeric sHsps 76) were further divided into five subclusters. Physicochemical properties, subcellular location predictions, and sequence conservation analyses provided insights into the differentiating elements of these putative functional groups. Strikingly, three of those subclusters included sHsps with features typical of metazoans, while the other two presented characteristics resembling non-metazoan proteins. This study provides a solid background for further research on the diversity, evolution, and function in the family of the sHsps. The characterized annelid sHsps are disclosed as essential for improving our understanding of this important family of proteins and their pleotropic functions. The features and the great diversity of annelid sHsps position them as potential powerful molecular biomarkers of environmental stress for acting as prognostic tool in a diverse range of environments.

RevDate: 2022-05-08

Nakajima T (2022)

Computation by inverse causality: A universal principle to produce symbols for the external reality in living systems.

Bio Systems pii:S0303-2647(22)00079-X [Epub ahead of print].

How can a living system escape the solipsistic self-making process? This problem has been ignored in mainstream biology. This study seeks a reasonable mechanism by which a living system produces symbols that signify external states. To this end, the inverse causality model proposed in previous studies was theoretically improved by refining the core concepts. Inverse causality is an epistemic principle operating in a subject system to produce symbols internally, signifying the past states of the external reality hidden to the subject. Inverse causality yields an important theorem for a system to produce symbols for external states. It asserts that if a system changes from state x to y1 in some instances, and from x to y2 in others, then x ⟼ y1 produces a symbol that signifies one external state, and x ⟼ y2 produces a different symbol for another state. The model postulates the equivalence principle in the subject-reality relationship, asserting that inverse causality is equivalent to causality in the external view. Living systems operate with inverse causality using biological devices called measurers, which include membrane receptors, second messengers, and molecular switches in cells, and neurons in multicellular organisms. A measurer is a medium of symbols signifying external states. Biological subsystems functioning as measurers are ubiquitous and essential in contemporary living systems for adaptation to their environments in particular ways by manipulating the symbols they produce. By the inverse causality operation, living systems can reduce the uncertainty of events and manage the probability distribution of future events favorable to survival and reproduction. Due to this function, their measurer systems were sophisticated and diversified in evolution. In philosophy and science, there has been endless debate between determinism and indeterminism. However, surprisingly, contemporary living systems use the inverse causality operation (ICW) to adapt to their environments, which is logically equivalent to the causal principle of determinism.

RevDate: 2022-05-06

Yuan F, Wang X, Zhao B, et al (2022)

The genome of the recretohalophyte Limonium bicolor provides insights into salt gland development and salinity adaptation during terrestrial evolution.

Molecular plant pii:S1674-2052(22)00148-4 [Epub ahead of print].

Halophytes have evolved specialized strategies to cope with high salinity. The extreme halophyte sea lavender (Limonium bicolor) lacks trichomes but possesses salt glands on its epidermis, which can excrete harmful ions such as sodium to avoid salt damage. Here, we report a high-quality, 2.92-Gb chromosome-scale L. bicolor genome assembly using a combination of Illumina short reads, single-molecule real-time long reads, chromosome conformation capture (Hi-C) data, and Bionano genome maps, which have greatly enriched genomic information of recretohalophyte with multicellular salt glands. Although the L. bicolor genome possesses genes showing similarity to trichome fate genes from Arabidopsis (Arabidopsis thaliana), it lacks homologs of the decision fate genes GLABRA3, ENHANCER OF GLABRA3, GLABRA2, TRANSPARENT TESTA GLABRA2, and SIAMESE, providing a molecular explanation for the absence of trichomes in this species. We identified key genes (LbHLH and LbTTG1) controlling salt gland development among classical trichome homologous genes and confirmed their roles by showing that their mutation markedly disrupted salt gland initiation, salt secretion and salt tolerance, thus offering the genetic support for the long-standing hypothesis that salt glands and trichomes may share a common origin. In addition, a whole-genome duplication event occurred in the L. bicolor genome after its divergence from Tartary buckwheat, which may have contributed to its adaptation to high salinity. The L. bicolor genome resource gives profound insights into plant salt tolerance mechanisms that should facilitate the engineering of salt-tolerant crops.

RevDate: 2022-05-03

Reyes-Rivera J, Wu Y, Guthrie BGH, et al (2022)

Nitric oxide signaling controls collective contractions in a colonial choanoflagellate.

Current biology : CB pii:S0960-9822(22)00586-3 [Epub ahead of print].

Although signaling by the gaseous molecule nitric oxide (NO) regulates key physiological processes in animals, including contractility,1-3 immunity,4,5 development,6-9 and locomotion,10,11 the early evolution of animal NO signaling remains unclear. To reconstruct the role of NO in the animal stem lineage, we set out to study NO signaling in choanoflagellates, the closest living relatives of animals.12 In animals, NO produced by the nitric oxide synthase (NOS) canonically signals through cGMP by activating soluble guanylate cyclases (sGCs).13,14 We surveyed the distribution of the NO signaling pathway components across the diversity of choanoflagellates and found three species that express NOS (of either bacterial or eukaryotic origin), sGCs, and downstream genes previously shown to be involved in the NO/cGMP pathway. One of the species coexpressing sGCs and a bacterial-type NOS, Choanoeca flexa, forms multicellular sheets that undergo collective contractions controlled by cGMP.15 We found that treatment with NO induces cGMP synthesis and contraction in C. flexa. Biochemical assays show that NO directly binds C. flexa sGC1 and stimulates its cyclase activity. The NO/cGMP pathway acts independently from other inducers of C. flexa contraction, including mechanical stimuli and heat, but sGC activity is required for contractions induced by light-to-dark transitions. The output of NO signaling in C. flexa-contractions resulting in a switch from feeding to swimming-resembles the effect of NO in sponges1-3 and cnidarians,11,16,17 where it interrupts feeding and activates contractility. These data provide insights into the biology of the first animals and the evolution of NO signaling.

RevDate: 2022-04-28

Goymer P (2022)

Multicellularity gets real.

Nature ecology & evolution pii:10.1038/s41559-022-01765-4 [Epub ahead of print].

RevDate: 2022-04-28

Farkas Z, Kovács K, Sarkadi Z, et al (2022)

Gene loss and compensatory evolution promotes the emergence of morphological novelties in budding yeast.

Nature ecology & evolution [Epub ahead of print].

Deleterious mutations are generally considered to be irrelevant for morphological evolution. However, they could be compensated by conditionally beneficial mutations, thereby providing access to new adaptive paths. Here we use high-dimensional phenotyping of laboratory-evolved budding yeast lineages to demonstrate that new cellular morphologies emerge exceptionally rapidly as a by-product of gene loss and subsequent compensatory evolution. Unexpectedly, the capacities for invasive growth, multicellular aggregation and biofilm formation also spontaneously evolve in response to gene loss. These multicellular phenotypes can be achieved by diverse mutational routes and without reactivating the canonical regulatory pathways. These ecologically and clinically relevant traits originate as pleiotropic side effects of compensatory evolution and have no obvious utility in the laboratory environment. The extent of morphological diversity in the evolved lineages is comparable to that of natural yeast isolates with diverse genetic backgrounds and lifestyles. Finally, we show that both the initial gene loss and subsequent compensatory mutations contribute to new morphologies, with their synergistic effects underlying specific morphological changes. We conclude that compensatory evolution is a previously unrecognized source of morphological diversity and phenotypic novelties.

RevDate: 2022-04-28

Zhang Z, Shitut S, Claushuis B, et al (2022)

Mutational meltdown of putative microbial altruists in Streptomyces coelicolor colonies.

Nature communications, 13(1):2266.

In colonies of the filamentous multicellular bacterium Streptomyces coelicolor, a subpopulation of cells arises that hyperproduces metabolically costly antibiotics, resulting in a division of labor that increases colony fitness. Because these cells contain large genomic deletions that cause massive reductions to individual fitness, their behavior is similar to altruistic worker castes in social insects or somatic cells in multicellular organisms. To understand these mutant cells' reproductive and genomic fate after their emergence, we use experimental evolution by serially transferring populations via spore-to-spore transfer for 25 cycles, reflective of the natural mode of bottlenecked transmission for these spore-forming bacteria. We show that in contrast to wild-type cells, putatively altruistic mutant cells continue to decline in fitness during transfer while they lose more fragments from their chromosome ends. In addition, the base-substitution rate in mutants increases roughly 10-fold, possibly due to mutations in genes for DNA replication and repair. Ecological damage, caused by reduced sporulation, coupled with DNA damage due to point mutations and deletions, leads to an inevitable and irreversible type of mutational meltdown in these cells. Taken together, these results suggest the cells arising in the S. coelicolor division of labor are analogous to altruistic reproductively sterile castes of social insects.

RevDate: 2022-04-26

Chaigne A, T Brunet (2022)

Incomplete abscission and cytoplasmic bridges in the evolution of eukaryotic multicellularity.

Current biology : CB, 32(8):R385-R397.

The textbook view of cell division terminates with the final separation of the two daughter cells in the process called abscission. However, in contrast to this classical view, a variety of cell types in multicellular organisms are connected through cytoplasmic bridges, which most often form by incomplete abscission or - more rarely - by local fusion of plasma membranes. In this review, we survey the distribution, function, and formation of cytoplasmic bridges across the eukaryotic tree of life. We find that cytoplasmic bridges are widespread, and were likely ancestrally present, in almost all lineages of eukaryotes with clonal multicellularity - including the five 'complex multicellular' lineages: animals, fungi, land plants, red algae, and brown algae. In animals, cytoplasmic bridges resulting from incomplete abscission are ubiquitous in the germline and common in pluripotent cell types. Although cytoplasmic bridges have been less studied than other structural mediators of multicellularity (such as adhesion proteins and extracellular matrix), we propose that they have played a pivotal role in the repeated evolution of eukaryotic clonal multicellularity - possibly by first performing a structural role and later by allowing exchange of nutrients and/or intercellular communication, which notably buffered cell-cell competition by averaging gene expression. Bridges were eventually lost from many animal tissues in concert with the evolution of spatial cell differentiation, cell motility within the organism, and other mechanisms for intercellular distribution of signals and metabolites. Finally, we discuss the molecular basis for the evolution of incomplete abscission and examine the alternative hypotheses of single or multiple origins.

RevDate: 2022-04-26

Mulcahey PJ, Chen Y, Driscoll N, et al (2022)

Multimodal, multiscale insights into hippocampal seizures enabled by transparent, graphene-based microelectrode arrays.

eNeuro pii:ENEURO.0386-21.2022 [Epub ahead of print].

Hippocampal seizures are a defining feature of mesial temporal lobe epilepsy. Area CA1 of the hippocampus is commonly implicated in the generation of seizures, which may occur due to the activity of endogenous cell populations or of inputs from other regions within the hippocampal formation. Simultaneously observing activity at the cellular and network scales in vivo remains challenging. Here, we present a novel technology for simultaneous electrophysiology and multicellular calcium imaging of CA1 pyramidal cells in mice enabled by a transparent graphene-based microelectrode array. We examine pyramidal cell firing at seizure onset, oscillatory coupling, and the dynamics of the seizure traveling wave as seizures evolve. Finally, we couple features derived from both modalities to predict the speed of the traveling wave using bootstrap aggregated regression trees. Analysis of the most important features in the regression trees suggests a transition among states in the evolution of hippocampal seizures.Significance StatementThere is a pressing need to develop novel technological strategies to integrate modalities towards greater mechanistic understanding of neuronal activities and brain computer interfacing applications. Our study provides an important advance by introducing a cannula imaging window/transparent electrode assembly to perform simultaneous multimodal measurements within mouse hippocampus. Performing and making sense of simultaneous measurements from the scale of single cells to a network level remains a substantial technical and conceptual challenge. Coupling measurements made by our methodology with an interpretable machine learning algorithm allows us to overcome this problem and posit a role of inhibition during hippocampal seizures.

RevDate: 2022-04-25

Melnikov NP, Bolshakov FV, Frolova VS, et al (2022)

Tissue homeostasis in sponges: Quantitative analysis of cell proliferation and apoptosis.

Journal of experimental zoology. Part B, Molecular and developmental evolution [Epub ahead of print].

Tissues of multicellular animals are maintained due to a tight balance between cell proliferation and programmed cell death. Sponges are early branching metazoans essential to understanding the key mechanisms of tissue homeostasis. This article is dedicated to the comparative analysis of proliferation and apoptosis in intact tissues of two sponges, Halisarca dujardinii (class Demospongiae) and Leucosolenia variabilis (class Calcarea). Labeled nucleotides EdU and anti-phosphorylated histone 3 antibodies reveal a considerable number of cycling cells in intact tissues of both species. Quantitative DNA staining reveals the classic cell cycle distribution curve. The main type of cycling cells are choanocytes - flagellated cells of the aquiferous system. The rate of proliferation remains constant throughout various areas of sponge bodies that contain choanocytes. The EdU tracking experiments conducted in H. dujardinii indicate that choanocytes may give rise to mesohyl cells through migration. The number of apoptotic cells in tissues of both species is insignificant, although being comparable to the renewing tissues of other animals. In vivo studies with tetramethylrhodamine ethyl ester and CellEvent Caspase-3/7 indicate that apoptosis might be independent of mitochondrial outer membrane permeabilization. Altogether, a combination of confocal laser scanning microscopy and flow cytometry provides a quantitative description of cell proliferation and apoptosis in sponges displaying either rapid growth or cell turnover.

RevDate: 2022-04-21

Gates C, Ananyev G, Roy-Chowdhury S, et al (2022)

Why Did Nature Choose Manganese over Cobalt to Make Oxygen Photosynthetically on the Earth?.

The journal of physical chemistry. B [Epub ahead of print].

All contemporary oxygenic phototrophs─from primitive cyanobacteria to complex multicellular plants─split water using a single invariant cluster comprising Mn4CaO5 (the water oxidation catalyst) as the catalyst within photosystem II, the universal oxygenic reaction center of natural photosynthesis. This cluster is unstable outside of PSII and can be reconstituted, both in vivo and in vitro, using elemental aqueous ions and light, via photoassembly. Here, we demonstrate the first functional substitution of manganese in any oxygenic reaction center by in vitro photoassembly. Following complete removal of inorganic cofactors from cyanobacterial photosystem II microcrystal (PSIIX), photoassembly with free cobalt (Co2+), calcium (Ca2+), and water (OH-) restores O2 evolution activity. Photoassembly occurs at least threefold faster using Co2+ versus Mn2+ due to a higher quantum yield for PSIIX-mediated charge separation (P*): Co2+ → P* → Co3+QA-. However, this kinetic preference for Co2+ over native Mn2+ during photoassembly is offset by significantly poorer catalytic activity (∼25% of the activity with Mn2+) and ∼3- to 30-fold faster photoinactivation rate. The resulting reconstituted Co-PSIIX oxidizes water by the standard four-flash photocycle, although they produce 4-fold less O2 per PSII, suggested to arise from faster charge recombination (Co3+QA ← Co4+QA-) in the catalytic cycle. The faster photoinactivation of reconstituted Co-PSIIX occurs under anaerobic conditions during the catalytic cycle, suggesting direct photodamage without the involvement of O2. Manganese offers two advantages for oxygenic phototrophs, which may explain its exclusive retention throughout Darwinian evolution: significantly slower charge recombination (Mn3+QA ← Mn4+QA-) permits more water oxidation at low and fluctuating solar irradiation (greater net energy conversion) and much greater tolerance to photodamage at high light intensities (Mn4+ is less oxidizing than Co4+). Future work to identify the chemical nature of the intermediates will be needed for further interpretation.

RevDate: 2022-04-18
CmpDate: 2022-04-18

Nozaki H, Mori F, Tanaka Y, et al (2022)

Cryopreservation of vegetative cells and zygotes of the multicellular volvocine green alga Gonium pectorale.

BMC microbiology, 22(1):103.

BACKGROUND: Colonial and multicellular volvocine green algae have been extensively studied recently in various fields of the biological sciences. However, only one species (Pandorina morum) has been cryopreserved in public culture collections.

RESULTS: Here, we investigated conditions for cryopreservation of the multicellular volvocine alga Gonium pectorale using vegetative colonies or cells and zygotes. Rates of vegetative cell survival in a G. pectorale strain after two-step cooling and freezing in liquid nitrogen were compared between different concentrations (3% and 6%) of the cryoprotectant N,N-dimethylformamide (DMF) and two types of tubes (0.2-mL polymerase chain reaction tubes and 2-mL cryotubes) used for cryopreservation. Among the four conditions investigated, the highest rate of survival [2.7 ± 3.6% (0.54-10%) by the most probable number (MPN) method] was obtained when 2.0-mL cryotubes containing 1.0 mL of culture samples with 6% DMF were subjected to cryogenic treatment. Using these optimized cryopreservation conditions, survival rates after freezing in liquid nitrogen were examined for twelve other strains of G. pectorale and twelve strains of five other Gonium species. We obtained ≥ 0.1% MPN survival in nine of the twelve G. pectorale strains tested. However, < 0.1% MPN survival was detected in eleven of twelve strains of five other Gonium species. In total, ten cryopreserved strains of G. pectorale were newly established in the Microbial Culture Collection at the National Institute for Environmental Studies. Although the cryopreservation of zygotes of volvocine algae has not been previously reported, high rates (approximately 60%) of G. pectorale zygote germination were observed after thawing zygotes that had been cryopreserved with 5% or 10% methanol as the cryoprotectant during two-step cooling and freezing in liquid nitrogen.

CONCLUSIONS: The present study demonstrated that cryopreservation of G. pectorale is possible with 6% DMF as a cryoprotectant and 1.0-mL culture samples in 2.0-mL cryotubes subjected to two-step cooling in a programmable freezer.

RevDate: 2022-04-16
CmpDate: 2022-04-15

Kambayashi C, Kakehashi R, Sato Y, et al (2022)

Geography-Dependent Horizontal Gene Transfer from Vertebrate Predators to Their Prey.

Molecular biology and evolution, 39(4):.

Horizontal transfer (HT) of genes between multicellular animals, once thought to be extremely rare, is being more commonly detected, but its global geographic trend and transfer mechanism have not been investigated. We discovered a unique HT pattern of Bovine-B (BovB) LINE retrotransposons in vertebrates, with a bizarre transfer direction from predators (snakes) to their prey (frogs). At least 54 instances of BovB HT were detected, which we estimate to have occurred across time between 85 and 1.3 Ma. Using comprehensive transcontinental sampling, our study demonstrates that BovB HT is highly prevalent in one geographical region, Madagascar, suggesting important regional differences in the occurrence of HTs. We discovered parasite vectors that may plausibly transmit BovB and found that the proportion of BovB-positive parasites is also high in Madagascar where BovB thus might be physically transported by parasites to diverse vertebrates, potentially including humans. Remarkably, in two frog lineages, BovB HT occurred after migration from a non-HT area (Africa) to the HT hotspot (Madagascar). These results provide a novel perspective on how the prevalence of parasites influences the occurrence of HT in a region, similar to pathogens and their vectors in some endemic diseases.

RevDate: 2022-04-18
CmpDate: 2022-04-18

Simon-Soro A, Ren Z, Krom BP, et al (2022)

Polymicrobial Aggregates in Human Saliva Build the Oral Biofilm.

mBio, 13(1):e0013122.

Biofilm community development has been established as a sequential process starting from the attachment of single cells on a surface. However, microorganisms are often found as aggregates in the environment and in biological fluids. Here, we conduct a comprehensive analysis of the native structure and composition of aggregated microbial assemblages in human saliva and investigate their spatiotemporal attachment and biofilm community development. Using multiscale imaging, cell sorting, and computational approaches combined with sequencing analysis, a diverse mixture of aggregates varying in size, structure, and microbial composition, including bacteria associated with host epithelial cells, can be found in saliva in addition to a few single-cell forms. Phylogenetic analysis reveals a mixture of complex consortia of aerobes and anaerobes in which bacteria traditionally considered early and late colonizers are found mixed together. When individually tracked during colonization and biofilm initiation, aggregates rapidly proliferate and expand tridimensionally, modulating population growth, spatial organization, and community scaffolding. In contrast, most single cells remain static or are incorporated by actively growing aggregates. These results suggest an alternative biofilm development process whereby aggregates containing different species or associated with human cells collectively adhere to the surface as "growth nuclei" to build the biofilm and shape polymicrobial communities at various spatial and taxonomic scales. IMPORTANCE Microbes in biological fluids can be found as aggregates. How these multicellular structures bind to surfaces and initiate the biofilm life cycle remains understudied. Here, we investigate the structural organization of microbial aggregates in human saliva and their role in biofilm formation. We found diverse mixtures of aggregates with different sizes, structures, and compositions in addition to free-living cells. When individually tracked during binding and growth on tooth-like surfaces, most aggregates developed into structured biofilm communities, whereas most single cells remained static or were engulfed by the growing aggregates. Our results reveal that preformed microbial consortia adhere as "buds of growth," governing biofilm initiation without specific taxonomic order or cell-by-cell succession, which provide new insights into spatial and population heterogeneity development in complex ecosystems.

RevDate: 2022-04-14

Rohkin Shalom S, Weiss B, Lalzar M, et al (2022)

Abundance and Localization of Symbiotic Bacterial Communities in the Fly Parasitoid Spalangia cameroni.

Applied and environmental microbiology [Epub ahead of print].

Multicellular eukaryotes often host multiple microbial symbionts that may cooperate or compete for host resources, such as space and nutrients. Here, we studied the abundances and localization of four bacterial symbionts, Rickettsia, Wolbachia, Sodalis, and Arsenophonus, in the parasitic wasp Spalangia cameroni. Using quantitative PCR (qPCR), we measured the symbionts' titers in wasps that harbor different combinations of these symbionts. We found that the titer of each symbiont decreased as the number of symbiont species in the community increased. Symbionts' titers were higher in females than in males. Rickettsia was the most abundant symbiont in all the communities, followed by Sodalis and Wolbachia. The titers of these three symbionts were positively correlated in some of the colonies. Fluorescence in situ hybridization was in line with the qPCR results: Rickettsia, Wolbachia, and Sodalis were observed in high densities in multiple organs, including brain, muscles, gut, Malpighian tubules, fat body, ovaries, and testes, while Arsenophonus was localized to fewer organs and in lower densities. Sodalis and Arsenophonus were observed in ovarian follicle cells but not within oocytes or laid eggs. This study highlights the connection between symbionts' abundance and localization. We discuss the possible connections between our findings to symbiont transmission success. IMPORTANCE Many insects carry intracellular bacterial symbionts (bacteria that reside within the cells of the insect). When multiple symbiont species cohabit in a host, they may compete or cooperate for space, nutrients, and transmission, and the nature of such interactions would be reflected in the abundance of each symbiont species. Given the widespread occurrence of coinfections with maternally transmitted symbionts in insects, it is important to learn more about how they interact, where they are localized, and how these two aspects affect their co-occurrence within individual insects. Here, we studied the abundance and the localization of four symbionts, Rickettsia, Wolbachia, Sodalis, and Arsenophonus, that cohabit the parasitic wasp Spalangia cameroni. We found that symbionts' titers differed between symbiotic communities. These results were corroborated by microscopy, which shows differential localization patterns. We discuss the findings in the contexts of community ecology, possible symbiont-symbiont interactions, and host control mechanisms that may shape the symbiotic community structure.

RevDate: 2022-04-14

Lin Y, Xu X, Maróti G, et al (2022)

Adaptation and phenotypic diversification of Bacillus thuringiensis biofilm are accompanied by fuzzy spreader morphotypes.

NPJ biofilms and microbiomes, 8(1):27.

Bacillus cereus group (Bacillus cereus sensu lato) has a diverse ecology, including various species that produce biofilms on abiotic and biotic surfaces. While genetic and morphological diversification enables the adaptation of multicellular communities, this area remains largely unknown in the Bacillus cereus group. In this work, we dissected the experimental evolution of Bacillus thuringiensis 407 Cry- during continuous recolonization of plastic beads. We observed the evolution of a distinct colony morphotype that we named fuzzy spreader (FS) variant. Most multicellular traits of the FS variant displayed higher competitive ability versus the ancestral strain, suggesting an important role for diversification in the adaptation of B. thuringiensis to the biofilm lifestyle. Further genetic characterization of FS variant revealed the disruption of a guanylyltransferase gene by an insertion sequence (IS) element, which could be similarly observed in the genome of a natural isolate. The evolved FS and the deletion mutant in the guanylyltransferase gene (Bt407ΔrfbM) displayed similarly altered aggregation and hydrophobicity compared to the ancestor strain, suggesting that the adaptation process highly depends on the physical adhesive forces.

RevDate: 2022-04-13
CmpDate: 2022-04-13

Shapiro JA (2022)

What we have learned about evolutionary genome change in the past 7 decades.

Bio Systems, 215-216:104669.

Cytogenetics and genomics have completely transformed our understanding of evolutionary genome change since the early 1950s. The point of this paper is to outline some of the empirical findings responsible for that transformation. The discovery of transposable elements (TEs) in maize by McClintock, and their subsequent rediscovery in all forms of life, tell us that organisms have the inherent capacity to evolve dispersed genomic networks encoding complex cellular and multicellular adaptations. Genomic analysis confirms the role of TEs in wiring novel networks at major evolutionary transitions. TEs and other forms of repetitive DNA are also important contributors to genome regions that serve as transcriptional templates for regulatory and other biologically functional noncoding ncRNAs. The many functions documented for ncRNAs shows the concept of abundant "selfish" or "junk" DNA in complex genomes is mistaken. Natural and artificial speciation by interspecific hybridization demonstrates that TEs and other biochemical systems of genome restructuring are subject to rapid activation and can generate changes throughout the genomes of the novel species that emerge. In addition to TEs and hybrid species, cancer cells have taught us important lessons about chromothripsis, chromoplexy and other forms of non-random multisite genome restructuring. In many of these restructured genomes, alternative end-joining processes display the capacities of eukaryotes to generate novel combinations of templated and untemplated DNA sequences at the sites of break repair. Sequence innovation by alternative end-joining is widespread among eukaryotes from single cells to advanced plants and animals. In sum, the cellular and genomic capacities of eukaryotic cells have proven to be capable of executing rapid macroevolutionary change under a variety of conditions.

RevDate: 2022-04-12

Kasperski A (2022)

Life Entrapped in a Network of Atavistic Attractors: How to Find a Rescue.

International journal of molecular sciences, 23(7): pii:ijms23074017.

In view of unified cell bioenergetics, cell bioenergetic problems related to cell overenergization can cause excessive disturbances in current cell fate and, as a result, lead to a change of cell-fate. At the onset of the problem, cell overenergization of multicellular organisms (especially overenergization of mitochondria) is solved inter alia by activation and then stimulation of the reversible Crabtree effect by cells. Unfortunately, this apparently good solution can also lead to a much bigger problem when, despite the activation of the Crabtree effect, cell overenergization persists for a long time. In such a case, cancer transformation, along with the Warburg effect, may occur to further reduce or stop the charging of mitochondria by high-energy molecules. Understanding the phenomena of cancer transformation and cancer development has become a real challenge for humanity. To date, many models have been developed to understand cancer-related mechanisms. Nowadays, combining all these models into one coherent universal model of cancer transformation and development can be considered a new challenge. In this light, the aim of this article is to present such a potentially universal model supported by a proposed new model of cellular functionality evolution. The methods of fighting cancer resulting from unified cell bioenergetics and the two presented models are also considered.

RevDate: 2022-04-12

Zschüntzsch J, Meyer S, Shahriyari M, et al (2022)

The Evolution of Complex Muscle Cell In Vitro Models to Study Pathomechanisms and Drug Development of Neuromuscular Disease.

Cells, 11(7): pii:cells11071233.

Many neuromuscular disease entities possess a significant disease burden and therapeutic options remain limited. Innovative human preclinical models may help to uncover relevant disease mechanisms and enhance the translation of therapeutic findings to strengthen neuromuscular disease precision medicine. By concentrating on idiopathic inflammatory muscle disorders, we summarize the recent evolution of the novel in vitro models to study disease mechanisms and therapeutic strategies. A particular focus is laid on the integration and simulation of multicellular interactions of muscle tissue in disease phenotypes in vitro. Finally, the requirements of a neuromuscular disease drug development workflow are discussed with a particular emphasis on cell sources, co-culture systems (including organoids), functionality, and throughput.

RevDate: 2022-04-09

Koide RT (2022)

On Holobionts, Holospecies, and Holoniches: the Role of Microbial Symbioses in Ecology and Evolution.

Microbial ecology [Epub ahead of print].

My goal in writing this is to increase awareness of the roles played by microbial symbionts in eukaryote ecology and evolution. Most eukaryotes host one or more species of symbiotic microorganisms, including prokaryotes and fungi. Many of these have profound impacts on the biology of their hosts. For example, microbial symbionts may expand the niches of their hosts, cause rapid adaptation of the host to the environment and re-adaptation to novel conditions via symbiont swapping, facilitate speciation, and fundamentally alter our concept of the species. In some cases, microbial symbionts and multicellular eukaryote hosts have a mutual dependency, which has obvious conservation implications. Hopefully, this contribution will stimulate a reevaluation of important ecological and evolutionary concepts including niche, adaptation, the species, speciation, and conservation of multicellular eukaryotes.

RevDate: 2022-04-08

Yang Y, H Jiang (2022)

Intercellular water exchanges trigger soliton-like waves in multicellular systems.

Biophysical journal pii:S0006-3495(22)00279-X [Epub ahead of print].

Oscillations and waves are ubiquitous in living cellular systems. Generations of these spatio-temporal patterns are generally attributed to some mechanochemical feedbacks. Here, we treat cells as open systems, i.e., water and ions can pass through the cell membrane passively or actively, and reveal a new origin of wave generation. We show that osmotic shocks above a shock threshold will trigger self-sustained cell oscillations and result in long-range waves propagating without decrement, a phenomenon that is analogous to the excitable medium. The travelling wave propagates along intercellular osmotic pressure gradient and its wave speed scales with the magnitude of intercellular water flows. Furthermore, we also find that the travelling wave exhibits several hallmarks of solitary waves. Together, our findings predict a new mechanism of wave generation in living multicellular systems. The ubiquity of intercellular water exchanges implies that this mechanism may be relevant to a broad class of systems.

RevDate: 2022-04-08

Dupin A, Aufinger L, Styazhkin I, et al (2022)

Synthetic cell-based materials extract positional information from morphogen gradients.

Science advances, 8(14):eabl9228.

Biomaterials composed of synthetic cells have the potential to adapt and differentiate guided by physicochemical environmental cues. Inspired by biological systems in development, which extract positional information (PI) from morphogen gradients in the presence of uncertainties, we here investigate how well synthetic cells can determine their position within a multicellular structure. To calculate PI, we created and analyzed a large number of synthetic cellular assemblies composed of emulsion droplets connected via lipid bilayer membranes. These droplets contained cell-free feedback gene circuits that responded to gradients of a genetic inducer acting as a morphogen. PI is found to be limited by gene expression noise and affected by the temporal evolution of the morphogen gradient and the cell-free expression system itself. The generation of PI can be rationalized by computational modeling of the system. We scale our approach using three-dimensional printing and demonstrate morphogen-based differentiation in larger tissue-like assemblies.

RevDate: 2022-04-08

Nagy K, Dukic B, Hodula O, et al (2022)

Emergence of Resistant Escherichia coli Mutants in Microfluidic On-Chip Antibiotic Gradients.

Frontiers in microbiology, 13:820738.

Spatiotemporal structures and heterogeneities are common in natural habitats, yet their role in the evolution of antibiotic resistance is still to be uncovered. We applied a microfluidic gradient generator device to study the emergence of resistant bacteria in spatial ciprofloxacin gradients. We observed biofilm formation in regions with sub-inhibitory concentrations of antibiotics, which quickly expanded into the high antibiotic regions. In the absence of an explicit structure of the habitat, this multicellular formation led to a spatial structure of the population with local competition and limited migration. Therefore, such structures can function as amplifiers of selection and aid the spread of beneficial mutations. We found that the physical environment itself induces stress-related mutations that later prove beneficial when cells are exposed to antibiotics. This shift in function suggests that exaptation occurs in such experimental scenarios. The above two processes pave the way for the subsequent emergence of highly resistant specific mutations.

RevDate: 2022-04-08
CmpDate: 2022-04-08

Ribba AS, Fraboulet S, Sadoul K, et al (2022)

The Role of LIM Kinases during Development: A Lens to Get a Glimpse of Their Implication in Pathologies.

Cells, 11(3):.

The organization of cell populations within animal tissues is essential for the morphogenesis of organs during development. Cells recognize three-dimensional positions with respect to the whole organism and regulate their cell shape, motility, migration, polarization, growth, differentiation, gene expression and cell death according to extracellular signals. Remodeling of the actin filaments is essential to achieve these cell morphological changes. Cofilin is an important binding protein for these filaments; it increases their elasticity in terms of flexion and torsion and also severs them. The activity of cofilin is spatiotemporally inhibited via phosphorylation by the LIM domain kinases 1 and 2 (LIMK1 and LIMK2). Phylogenetic analysis indicates that the phospho-regulation of cofilin has evolved as a mechanism controlling the reorganization of the actin cytoskeleton during complex multicellular processes, such as those that occur during embryogenesis. In this context, the main objective of this review is to provide an update of the respective role of each of the LIM kinases during embryonic development.

RevDate: 2022-04-07

van der Zee MJ, Whiting JR, Paris JR, et al (2022)

Rapid genomic convergent evolution in experimental populations of Trinidadian guppies (Poecilia reticulata).

Evolution letters, 6(2):149-161 pii:EVL3272.

Although rapid phenotypic evolution has been documented often, the genomic basis of rapid adaptation to natural environments is largely unknown in multicellular organisms. Population genomic studies of experimental populations of Trinidadian guppies (Poecilia reticulata) provide a unique opportunity to study this phenomenon. Guppy populations that were transplanted from high-predation (HP) to low-predation (LP) environments have been shown to evolve toward the phenotypes of naturally colonized LP populations in as few as eight generations. These changes persist in common garden experiments, indicating that they have a genetic basis. Here, we report results of whole genome variation in four experimental populations colonizing LP sites along with the corresponding HP source population. We examined genome-wide patterns of genetic variation to estimate past demography and used a combination of genome scans, forward simulations, and a novel analysis of allele frequency change vectors to uncover the signature of selection. We detected clear signals of population growth and bottlenecks at the genome-wide level that matched the known history of population numbers. We found a region on chromosome 15 under strong selection in three of the four populations and with our multivariate approach revealing subtle parallel changes in allele frequency in all four populations across this region. Investigating patterns of genome-wide selection in this uniquely replicated experiment offers remarkable insight into the mechanisms underlying rapid adaptation, providing a basis for comparison with other species and populations experiencing rapidly changing environments.

RevDate: 2022-04-07
CmpDate: 2022-04-07

Verdonck R, Legrand D, Jacob S, et al (2022)

Phenotypic plasticity through disposable genetic adaptation in ciliates.

Trends in microbiology, 30(2):120-130.

Ciliates have an extraordinary genetic system in which each cell harbors two distinct kinds of nucleus, a transcriptionally active somatic nucleus and a quiescent germline nucleus. The latter undergoes classical, heritable genetic adaptation, while adaptation of the somatic nucleus is only short-term and thus disposable. The ecological and evolutionary relevance of this nuclear dimorphism have never been well formalized, which is surprising given the long history of using ciliates such as Tetrahymena and Paramecium as model organisms. We present a novel, alternative explanation for ciliate nuclear dimorphism which, we argue, should be considered an instrument of phenotypic plasticity by somatic selection on the level of the ciliate clone, as if it were a diffuse multicellular organism. This viewpoint helps to put some enigmatic aspects of ciliate biology into perspective and presents the diversity of ciliates as a large natural experiment that we can exploit to study phenotypic plasticity and organismality.

RevDate: 2022-04-04

Chen K, Gao Y, Li L, et al (2022)

Increased Drug Resistance and Biofilm Formation Ability in ST34-Type Salmonella Typhimurium Exhibiting Multicellular Behavior in China.

Frontiers in microbiology, 13:876500.

Salmonella Typhimurium is an important food-borne pathogen. In this paper, multicellular behavior and associated characteristics of S. Typhimurium isolated from human and animal source food were studied. All the S. Typhimurium strains exhibiting multicellular behavior (100%) belonged to the ST34 type. In addition, most of the ST34-type multicellular behavior S. Typhimurium strains had a human origin (69.11%) and 98% of the ST34-type multicellular behavior strains exhibited strong biofilm formation capacity, which was much higher than that of non-multicellular behavior strains (7%, P < 0.01). Antibiotic resistance in ST34-type multicellular behavior strains was significantly higher than in strains with non-multicellular behavior for most conventional drugs (P < 0.05); notably, Polymyxin B (8%) and Imipenem (1%) resistances were also observed in the ST34-type strains. Furthermore, all the ST34-type multicellular behavior strains (100%) exhibited Multiple Drug Resistance (resistance to ≥3antibiotics), which was much higher than that of the non-multicellular behavior strains (P < 0.05). Consistent with the drug-resistant phenotype, the carrying rates of most drug-resistant genes in ST34-type multicellular behavior strains were higher than that those in non-multicellular behavior strains (P < 0.05). Therefore, this study revealed the emergence of a prevalent ST34-type multicellular behavior S. Typhimurium strains with increased biofilm formation ability and drug resistance rate, which poses a threat to public health safety, and highlights the need for comprehensive monitoring of the strains.

RevDate: 2022-04-01

Ramon-Mateu J, Edgar A, Mitchell D, et al (2022)

Studying Ctenophora WBR Using Mnemiopsis leidyi.

Methods in molecular biology (Clifton, N.J.), 2450:95-119.

Ctenophores, also known as comb jellies, are a clade of fragile holopelagic, carnivorous marine invertebrates, that represent one of the most ancient extant groups of multicellular animals. Ctenophores show a remarkable ability to regenerate in the adult form, being capable of replacing all body parts (i.e., whole-body regeneration) after loss/amputation. With many favorable experimental features (optical clarity, stereotyped cell lineage, multiple cell types), a full genome sequence available and their early branching phylogenetic position, ctenophores are well placed to provide information about the evolution of regenerative ability throughout the Metazoa. Here, we provide a collection of detailed protocols for use of the lobate ctenophore Mnemiopsis leidyi to study whole-body regeneration, including specimen collection, husbandry, surgical manipulation, and imaging techniques.

RevDate: 2022-03-30

Burnetti A, WC Ratcliff (2022)

Experimental evolution is not just for model organisms.

PLoS biology, 20(3):e3001587 pii:PBIOLOGY-D-22-00324.

In a new paper published in PLOS Biology, Dudin and colleagues evolve simple multicellularity in Sphaeroforma arctica, a unicellular relative of animals. This work establishes a new and open-ended avenue for examining the evolution of multicellularity in an important but understudied group of organisms.

RevDate: 2022-03-29

Dudin O, Wielgoss S, New AM, et al (2022)

Regulation of sedimentation rate shapes the evolution of multicellularity in a close unicellular relative of animals.

PLoS biology, 20(3):e3001551 pii:PBIOLOGY-D-21-03000.

Significant increases in sedimentation rate accompany the evolution of multicellularity. These increases should lead to rapid changes in ecological distribution, thereby affecting the costs and benefits of multicellularity and its likelihood to evolve. However, how genetic and cellular traits control this process, their likelihood of emergence over evolutionary timescales, and the variation in these traits as multicellularity evolves are still poorly understood. Here, using isolates of the ichthyosporean genus Sphaeroforma-close unicellular relatives of animals with brief transient multicellular life stages-we demonstrate that sedimentation rate is a highly variable and evolvable trait affected by at least 2 distinct physical mechanisms. First, we find extensive (>300×) variation in sedimentation rates for different Sphaeroforma species, mainly driven by size and density during the unicellular-to-multicellular life cycle transition. Second, using experimental evolution with sedimentation rate as a focal trait, we readily obtained, for the first time, fast settling and multicellular Sphaeroforma arctica isolates. Quantitative microscopy showed that increased sedimentation rates most often arose by incomplete cellular separation after cell division, leading to clonal "clumping" multicellular variants with increased size and density. Strikingly, density increases also arose by an acceleration of the nuclear doubling time relative to cell size. Similar size- and density-affecting phenotypes were observed in 4 additional species from the Sphaeroforma genus, suggesting that variation in these traits might be widespread in the marine habitat. By resequencing evolved isolates to high genomic coverage, we identified mutations in regulators of cytokinesis, plasma membrane remodeling, and chromatin condensation that may contribute to both clump formation and the increase in the nuclear number-to-volume ratio. Taken together, this study illustrates how extensive cellular control of density and size drive sedimentation rate variation, likely shaping the onset and further evolution of multicellularity.

RevDate: 2022-03-24
CmpDate: 2022-03-24

Varahan S, S Laxman (2021)

Bend or break: how biochemically versatile molecules enable metabolic division of labor in clonal microbial communities.

Genetics, 219(2):.

In fluctuating nutrient environments, isogenic microbial cells transition into "multicellular" communities composed of phenotypically heterogeneous cells, showing functional specialization. In fungi (such as budding yeast), phenotypic heterogeneity is often described in the context of cells switching between different morphotypes (e.g., yeast to hyphae/pseudohyphae or white/opaque transitions in Candida albicans). However, more fundamental forms of metabolic heterogeneity are seen in clonal Saccharomyces cerevisiae communities growing in nutrient-limited conditions. Cells within such communities exhibit contrasting, specialized metabolic states, and are arranged in distinct, spatially organized groups. In this study, we explain how such an organization can stem from self-organizing biochemical reactions that depend on special metabolites. These metabolites exhibit plasticity in function, wherein the same metabolites are metabolized and utilized for distinct purposes by different cells. This in turn allows cell groups to function as specialized, interdependent cross-feeding systems which support distinct metabolic processes. Exemplifying a system where cells exhibit either gluconeogenic or glycolytic states, we highlight how available metabolites can drive favored biochemical pathways to produce new, limiting resources. These new resources can themselves be consumed or utilized distinctly by cells in different metabolic states. This thereby enables cell groups to sustain contrasting, even apparently impossible metabolic states with stable transcriptional and metabolic signatures for a given environment, and divide labor in order to increase community fitness or survival. We speculate on possible evolutionary implications of such metabolic specialization and division of labor in isogenic microbial communities.

RevDate: 2022-03-23

Verkerke H, Dias-Baruffi M, Cummings RD, et al (2022)

Galectins: An Ancient Family of Carbohydrate Binding Proteins with Modern Functions.

Methods in molecular biology (Clifton, N.J.), 2442:1-40.

Galectins are a large family of carbohydrate binding proteins with members in nearly every lineage of multicellular life. Through tandem and en-mass genome duplications, over 15 known vertebrate galectins likely evolved from a single common ancestor extant in pre-chordate lineages. While galectins have divergently evolved numerous functions, some of which do not involve carbohydrate recognition, the vast majority of the galectins have retained the conserved ability to bind variably modified polylactosamine (polyLacNAc) residues on glycans that modify proteins and lipids on the surface of host cells and pathogens. In addition to their direct role in microbial killing, many proposed galectin functions in the immune system and cancer involve crosslinking glycosylated receptors and modifying signaling pathways or sensitivity to antigen from the outside in. However, a large body of work has uncovered intracellular galectin functions mediated by carbohydrate- and non-carbohydrate-dependent interactions. In the cytoplasm, galectins can tune intracellular kinase and G-protein-coupled signaling cascades important for nutrient sensing, cell cycle progression, and transformation. Particularly, but interconnected pathways, cytoplasmic galectins serve the innate immune system as sensors of endolysosomal damage, recruiting and assembling the components of autophagosomes during intracellular infection through carbohydrate-dependent and -independent activities. In the nucleus, galectins participate in pre-mRNA splicing perhaps through interactions with non-coding RNAs required for assembly of spliceosomes. Together, studies of galectin function paint a picture of a functionally dynamic protein family recruited during eons of evolution to regulate numerous essential cellular processes in the context of multicellular life.

RevDate: 2022-03-23

Hammond M, Dorrell RG, Speijer D, et al (2022)

Eukaryotic cellular intricacies shape mitochondrial proteomic complexity.

BioEssays : news and reviews in molecular, cellular and developmental biology [Epub ahead of print].

Mitochondria have been fundamental to the eco-physiological success of eukaryotes since the last eukaryotic common ancestor (LECA). They contribute essential functions to eukaryotic cells, above and beyond classical respiration. Mitochondria interact with, and complement, metabolic pathways occurring in other organelles, notably diversifying the chloroplast metabolism of photosynthetic organisms. Here, we integrate existing literature to investigate how mitochondrial metabolism varies across the landscape of eukaryotic evolution. We illustrate the mitochondrial remodelling and proteomic changes undergone in conjunction with major evolutionary transitions. We explore how the mitochondrial complexity of the LECA has been remodelled in specific groups to support subsequent evolutionary transitions, such as the acquisition of chloroplasts in photosynthetic species and the emergence of multicellularity. We highlight the versatile and crucial roles played by mitochondria during eukaryotic evolution, extending from its huge contribution to the development of the LECA itself to the dynamic evolution of individual eukaryote groups, reflecting both their current ecologies and evolutionary histories.

RevDate: 2022-03-23

Bogaert KA, Zakka EE, Coelho SM, et al (2022)

Polarization of brown algal zygotes.

Seminars in cell & developmental biology pii:S1084-9521(22)00075-1 [Epub ahead of print].

Brown algae are a group of multicellular, heterokont algae that have convergently evolved developmental complexity that rivals that of embryophytes, animals or fungi. Early in development, brown algal zygotes establish a basal and an apical pole, which will become respectively the basal system (holdfast) and the apical system (thallus) of the adult alga. Brown algae are interesting models for understanding the establishment of cell polarity in a broad evolutionary context, because they exhibit a large diversity of life cycles, reproductive strategies and, importantly, their zygotes are produced in large quantities free of parental tissue, with symmetry breaking and asymmetric division taking place in a highly synchronous manner. This review describes the current knowledge about the establishment of the apical-basal axis in the model brown seaweeds Ectocarpus, Dictyota, Fucus and Saccharina, highlighting the advantages and specific interests of each system. Ectocarpus is a genetic model system that allows access to the molecular basis of early development and life-cycle control over apical-basal polarity. The oogamous brown alga Fucus, together with emerging comparative models Dictyota and Saccharina, emphasize the diversity of strategies of symmetry breaking in determining a cell polarity vector in brown algae. A comparison with symmetry-breaking mechanisms in land plants, animals and fungi, reveals that the one-step zygote polarisation of Fucus compares well to Saccharomyces budding and Arabidopsis stomata development, while the two-phased symmetry breaking in the Dictyota zygote compares to Schizosaccharomyces fission, the Caenorhabditis anterior-posterior zygote polarisation and Arabidopsis prolate pollen polarisation. The apical-basal patterning in Saccharina zygotes on the other hand, may be seen as analogous to that of land plants. Overall, brown algae have the potential to bring exciting new information on how a single cell gives rise to an entire complex body plan.

RevDate: 2022-03-21

Chen C, Wang P, Chen H, et al (2022)

Smart Magnetotactic Bacteria Enable the Inhibition of Neuroblastoma under an Alternating Magnetic Field.

ACS applied materials & interfaces [Epub ahead of print].

Magnetotactic bacteria are ubiquitous microorganisms in nature that synthesize intracellular magnetic nanoparticles called magnetosomes in a gene-controlled way and arrange them in chains. From in vitro to in vivo, we demonstrate that the intact body of Magnetospirillum magneticum AMB-1 has potential as a natural magnetic hyperthermia material for cancer therapy. Compared to chains of magnetosomes and individual magnetosomes, the entire AMB-1 cell exhibits superior heating capability under an alternating magnetic field. When incubating with tumor cells, the intact AMB-1 cells disperse better than the other two types of magnetosomes, decreasing cellular viability under the control of an alternating magnetic field. Furthermore, in vivo experiments in nude mice with neuroblastoma found that intact AMB-1 cells had the best antitumor activity with magnetic hyperthermia therapy compared to other treatment groups. These findings suggest that the intact body of magnetotactic bacteria has enormous promise as a natural material for tumor magnetic hyperthermia. In biomedical applications, intact and living magnetotactic bacteria play an increasingly essential function as a targeting robot due to their magnetotaxis.

RevDate: 2022-03-17

Jiménez-Marín B, BJSC Olson (2022)

The Curious Case of Multicellularity in the Volvocine Algae.

Frontiers in genetics, 13:787665 pii:787665.

The evolution of multicellularity is a major evolutionary transition that underlies the radiation of many species in all domains of life, especially in eukaryotes. The volvocine green algae are an unconventional model system that holds great promise in the field given its genetic tractability, late transition to multicellularity, and phenotypic diversity. Multiple efforts at linking multicellularity-related developmental landmarks to key molecular changes, especially at the genome level, have provided key insights into the molecular innovations or lack thereof that underlie multicellularity. Twelve developmental changes have been proposed to explain the evolution of complex differentiated multicellularity in the volvocine algae. Co-option of key genes, such as cell cycle and developmental regulators has been observed, but with few exceptions, known co-option events do not seem to coincide with most developmental features observed in multicellular volvocines. The apparent lack of "master multicellularity genes" combined with no apparent correlation between gene gains for developmental processes suggest the possibility that many multicellular traits might be the product gene-regulatory and functional innovations; in other words, multicellularity can arise from shared genomic repertoires that undergo regulatory and functional overhauls.

RevDate: 2022-03-16
CmpDate: 2022-03-16

Day TC, Höhn SS, Zamani-Dahaj SA, et al (2022)

Cellular organization in lab-evolved and extant multicellular species obeys a maximum entropy law.

eLife, 11:.

The prevalence of multicellular organisms is due in part to their ability to form complex structures. How cells pack in these structures is a fundamental biophysical issue, underlying their functional properties. However, much remains unknown about how cell packing geometries arise, and how they are affected by random noise during growth - especially absent developmental programs. Here, we quantify the statistics of cellular neighborhoods of two different multicellular eukaryotes: lab-evolved 'snowflake' yeast and the green alga Volvox carteri. We find that despite large differences in cellular organization, the free space associated with individual cells in both organisms closely fits a modified gamma distribution, consistent with maximum entropy predictions originally developed for granular materials. This 'entropic' cellular packing ensures a degree of predictability despite noise, facilitating parent-offspring fidelity even in the absence of developmental regulation. Together with simulations of diverse growth morphologies, these results suggest that gamma-distributed cell neighborhood sizes are a general feature of multicellularity, arising from conserved statistics of cellular packing.

RevDate: 2022-03-16
CmpDate: 2022-03-16

Schiller EA, DT Bergstralh (2021)

Interaction between Discs large and Pins/LGN/GPSM2: a comparison across species.

Biology open, 10(11):.

The orientation of the mitotic spindle determines the direction of cell division, and therefore contributes to tissue shape and cell fate. Interaction between the multifunctional scaffolding protein Discs large (Dlg) and the canonical spindle orienting factor GPSM2 (called Pins in Drosophila and LGN in vertebrates) has been established in bilaterian models, but its function remains unclear. We used a phylogenetic approach to test whether the interaction is obligate in animals, and in particular whether Pins/LGN/GPSM2 evolved in multicellular organisms as a Dlg-binding protein. We show that Dlg diverged in C. elegans and the syncytial sponge Opsacas minuta and propose that this divergence may correspond with differences in spindle orientation requirements between these organisms and the canonical pathways described in bilaterians. We also demonstrate that Pins/LGN/GPSM2 is present in basal animals, but the established Dlg-interaction site cannot be found in either Placozoa or Porifera. Our results suggest that the interaction between Pins/LGN/GPSM2 and Dlg appeared in Cnidaria, and we therefore speculate that it may have evolved to promote accurate division orientation in the nervous system. This work reveals the evolutionary history of the Pins/LGN/GPSM2-Dlg interaction and suggests new possibilities for its importance in spindle orientation during epithelial and neural tissue development.

RevDate: 2022-03-14

Benureau FCY, J Tani (2022)

Morphological Development at the Evolutionary Timescale: Robotic Developmental Evolution.

Artificial life pii:109958 [Epub ahead of print].

Evolution and development operate at different timescales; generations for the one, a lifetime for the other. These two processes, the basis of much of life on earth, interact in many non-trivial ways, but their temporal hierarchy-evolution overarching development-is observed for most multicellular life forms. When designing robots, however, this tenet lifts: It becomes-however natural-a design choice. We propose to inverse this temporal hierarchy and design a developmental process happening at the phylogenetic timescale. Over a classic evolutionary search aimed at finding good gaits for tentacle 2D robots, we add a developmental process over the robots' morphologies. Within a generation, the morphology of the robots does not change. But from one generation to the next, the morphology develops. Much like we become bigger, stronger, and heavier as we age, our robots are bigger, stronger, and heavier with each passing generation. Our robots start with baby morphologies, and a few thousand generations later, end-up with adult ones. We show that this produces better and qualitatively different gaits than an evolutionary search with only adult robots, and that it prevents premature convergence by fostering exploration. In addition, we validate our method on voxel lattice 3D robots from the literature and compare it to a recent evolutionary developmental approach. Our method is conceptually simple, and it can be effective on small or large populations of robots, and intrinsic to the robot and its morphology, not the task or environment. Furthermore, by recasting the evolutionary search as a learning process, these results can be viewed in the context of developmental learning robotics.

RevDate: 2022-03-07

Palazzo AF, NS Kejiou (2022)

Non-Darwinian Molecular Biology.

Frontiers in genetics, 13:831068 pii:831068.

With the discovery of the double helical structure of DNA, a shift occurred in how biologists investigated questions surrounding cellular processes, such as protein synthesis. Instead of viewing biological activity through the lens of chemical reactions, this new field used biological information to gain a new profound view of how biological systems work. Molecular biologists asked new types of questions that would have been inconceivable to the older generation of researchers, such as how cellular machineries convert inherited biological information into functional molecules like proteins. This new focus on biological information also gave molecular biologists a way to link their findings to concepts developed by genetics and the modern synthesis. However, by the late 1960s this all changed. Elevated rates of mutation, unsustainable genetic loads, and high levels of variation in populations, challenged Darwinian evolution, a central tenant of the modern synthesis, where adaptation was the main driver of evolutionary change. Building on these findings, Motoo Kimura advanced the neutral theory of molecular evolution, which advocates that selection in multicellular eukaryotes is weak and that most genomic changes are neutral and due to random drift. This was further elaborated by Jack King and Thomas Jukes, in their paper "Non-Darwinian Evolution", where they pointed out that the observed changes seen in proteins and the types of polymorphisms observed in populations only become understandable when we take into account biochemistry and Kimura's new theory. Fifty years later, most molecular biologists remain unaware of these fundamental advances. Their adaptionist viewpoint fails to explain data collected from new powerful technologies which can detect exceedingly rare biochemical events. For example, high throughput sequencing routinely detects RNA transcripts being produced from almost the entire genome yet are present less than one copy per thousand cells and appear to lack any function. Molecular biologists must now reincorporate ideas from classical biochemistry and absorb modern concepts from molecular evolution, to craft a new lens through which they can evaluate the functionality of transcriptional units, and make sense of our messy, intricate, and complicated genome.

RevDate: 2022-03-05

Tong K, Bozdag GO, WC Ratcliff (2022)

Selective drivers of simple multicellularity.

Current opinion in microbiology, 67:102141 pii:S1369-5274(22)00018-2 [Epub ahead of print].

In order to understand the evolution of multicellularity, we must understand how and why selection favors the first steps in this process: the evolution of simple multicellular groups. Multicellularity has evolved many times in independent lineages with fundamentally different ecologies, yet no work has yet systematically examined these diverse selective drivers. Here we review recent developments in systematics, comparative biology, paleontology, synthetic biology, theory, and experimental evolution, highlighting ten selective drivers of simple multicellularity. Our survey highlights the many ecological opportunities available for simple multicellularity, and stresses the need for additional work examining how these first steps impact the subsequent evolution of complex multicellularity.

RevDate: 2022-03-05

Frenkel-Pinter M, Petrov AS, Matange K, et al (2022)

Adaptation and Exaptation: From Small Molecules to Feathers.

Journal of molecular evolution [Epub ahead of print].

Evolution works by adaptation and exaptation. At an organismal level, exaptation and adaptation are seen in the formation of organelles and the advent of multicellularity. At the sub-organismal level, molecular systems such as proteins and RNAs readily undergo adaptation and exaptation. Here we suggest that the concepts of adaptation and exaptation are universal, synergistic, and recursive and apply to small molecules such as metabolites, cofactors, and the building blocks of extant polymers. For example, adenosine has been extensively adapted and exapted throughout biological evolution. Chemical variants of adenosine that are products of adaptation include 2' deoxyadenosine in DNA and a wide array of modified forms in mRNAs, tRNAs, rRNAs, and viral RNAs. Adenosine and its variants have been extensively exapted for various functions, including informational polymers (RNA, DNA), energy storage (ATP), metabolism (e.g., coenzyme A), and signaling (cyclic AMP). According to Gould, Vrba, and Darwin, exaptation imposes a general constraint on interpretation of history and origins; because of exaptation, extant function should not be used to explain evolutionary history. While this notion is accepted in evolutionary biology, it can also guide the study of the chemical origins of life. We propose that (i) evolutionary theory is broadly applicable from the dawn of life to the present time from molecules to organisms, (ii) exaptation and adaptation were important and simultaneous processes, and (iii) robust origin of life models can be constructed without conflating extant utility with historical basis of origins.

RevDate: 2022-03-05

Li XG, Jiao ZX, Zhang HH, et al (2022)

Complete genome sequence of Crassaminicella sp. 143-21,isolated from a deep-sea hydrothermal vent.

Marine genomics, 62:100899.

Crassaminicella sp. 143-21, a putative new species isolated from deep-sea hydrothermal vent chimney on the Central Indian Ridge (CIR), is an anaerobic, thermophilic and rod-shaped bacterium belonging to the family Clostridiaceae. In this study, we present the complete genome sequence of strain 143-21, comprising 2,756,133 bp with a G + C content of 31.1%. In total, 2427 protein coding genes, 121 tRNA genes and 33 rRNA genes were obtained. Genomic analysis of strain 143-21 revealed that numerous genes related to organic matter transport and catabolism, including peptide transport, amino acid transport, saccharide transport, ethanolamine transport and corresponding metabolic pathways. Further, the genome contains a large proportion of genes involved in translation, ribosomal structure, and signal transduction. These genes might facilitate microbial survival in deep-sea hydrothermal vent environment. The genome of strain 143-21 will be helpful for further understanding its adaptive strategies in the deep-sea hydrothermal vent environment.

RevDate: 2022-03-04
CmpDate: 2022-03-04

Fernández LD, Seppey CVW, Singer D, et al (2022)

Niche Conservatism Drives the Elevational Diversity Gradient in Major Groups of Free-Living Soil Unicellular Eukaryotes.

Microbial ecology, 83(2):459-469.

Ancestral adaptations to tropical-like climates drive most multicellular biogeography and macroecology. Observational studies suggest that this niche conservatism could also be shaping unicellular biogeography and macroecology, although evidence is limited to Acidobacteria and testate amoebae. We tracked the phylogenetic signal of this niche conservatism in far related and functionally contrasted groups of common soil protists (Bacillariophyta, Cercomonadida, Ciliophora, Euglyphida and Kinetoplastida) along a humid but increasingly cold elevational gradient in Switzerland. Protist diversity decreased, and the size of the geographic ranges of taxa increased with elevation and associated decreasing temperature (climate), which is consistent with a macroecological pattern known as the Rapoport effect. Bacillariophyta exhibited phylogenetically overdispersed communities assembled by competitive exclusion of closely related taxa with shared (conserved) niches. By contrast, Cercomonadida, Ciliophora, Euglyphida and Kinetoplastida exhibited phylogenetically clustered communities assembled by habitat filtering, revealing the coexistence of closely related taxa with shared (conserved) adaptations to cope with the humid but temperate to cold climate of the study site. Phylobetadiversity revealed that soil protists exhibit a strong phylogenetic turnover among elevational sites, suggesting that most taxa have evolutionary constraints that prevent them from colonizing the colder and higher sites of the elevation gradient. Our results suggest that evolutionary constraints determine how soil protists colonize climates departing from warm and humid conditions. We posit that these evolutionary constraints are linked to an ancestral adaptation to tropical-like climates, which limits their survival in exceedingly cold sites. This niche conservatism possibly drives their biogeography and macroecology along latitudinal and altitudinal climatic gradients.

RevDate: 2022-03-02

Kwantes M, T Wichard (2022)

The APAF1_C/WD40 repeat domain-encoding gene from the sea lettuce Ulva mutabilis sheds light on the evolution of NB-ARC domain-containing proteins in green plants.

Planta, 255(4):76.

MAIN CONCLUSION: We advance Ulva's genetic tractability and highlight its value as a model organism by characterizing its APAF1_C/WD40 domain-encoding gene, which belongs to a family that bears homology to R genes. The multicellular chlorophyte alga Ulva mutabilis (Ulvophyceae, Ulvales) is native to coastal ecosystems worldwide and attracts both high socio-economic and scientific interest. To further understand the genetic mechanisms that guide its biology, we present a protocol, based on adapter ligation-mediated PCR, for retrieving flanking sequences in U. mutabilis vector-insertion mutants. In the created insertional library, we identified a null mutant with an insertion in an apoptotic protease activating factor 1 helical domain (APAF1_C)/WD40 repeat domain-encoding gene. Protein domain architecture analysis combined with phylogenetic analysis revealed that this gene is a member of a subfamily that arose early in the evolution of green plants (Viridiplantae) through the acquisition of a gene that also encoded N-terminal nucleotide-binding adaptor shared by APAF-1, certain R-gene products and CED-4 (NB-ARC) and winged helix-like (WH-like) DNA-binding domains. Although phenotypic analysis revealed no mutant phenotype, gene expression levels in control plants correlated to the presence of bacterial symbionts, which U. mutabilis requires for proper morphogenesis. In addition, our analysis led to the discovery of a putative Ulva nucleotide-binding site and leucine-rich repeat (NBS-LRR) Resistance protein (R-protein), and we discuss how the emergence of these R proteins in green plants may be linked to the evolution of the APAF1_C/WD40 protein subfamily.

RevDate: 2022-03-02

Gao Y, Pichugin Y, Gokhale CS, et al (2022)

Evolution of reproductive strategies in incipient multicellularity.

Journal of the Royal Society, Interface, 19(188):20210716.

Multicellular organisms potentially show a large degree of diversity in reproductive strategies, producing offspring with varying sizes and compositions compared to their unicellular ancestors. In reality, only a few of these reproductive strategies are prevalent. To understand why this could be the case, we develop a stage-structured population model to probe the evolutionary growth advantages of reproductive strategies in incipient multicellular organisms. The performance of reproductive strategies is evaluated by the growth rates of the corresponding populations. We identify the optimal reproductive strategy, leading to the largest growth rate for a population. Considering the effects of organism size and cellular interaction, we found that distinct reproductive strategies could perform uniquely or equally well under different conditions. If a single reproductive strategy is optimal, it is binary splitting, dividing into two parts. Our results show that organism size and cellular interaction can play crucial roles in shaping reproductive strategies in nascent multicellularity. Our model sheds light on understanding the mechanism driving the evolution of reproductive strategies in incipient multicellularity. Beyond multicellularity, our results imply that a crucial factor in the evolution of unicellular species' reproductive strategies is organism size.

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In the early 1990's, Robert Robbins was a faculty member at Johns Hopkins, where he directed the informatics core of GDB — the human gene-mapping database of the international human genome project. To share papers with colleagues around the world, he set up a small paper-sharing section on his personal web page. This small project evolved into The Electronic Scholarly Publishing Project.

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In 1995, Robbins became the VP/IT of the Fred Hutchinson Cancer Research Center in Seattle, WA. Soon after arriving in Seattle, Robbins secured funding, through the ELSI component of the US Human Genome Project, to create the original ESP.ORG web site, with the formal goal of providing free, world-wide access to the literature of classical genetics.

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When the site began, no journals were making their early content available in digital format. As a result, ESP was obliged to digitize classic literature before it could be made available. For many important papers — such as Mendel's original paper or the first genetic map — ESP had to produce entirely new typeset versions of the works, if they were to be available in a high-quality format.

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Early support from the DOE component of the Human Genome Project was critically important for getting the ESP project on a firm foundation. Since that funding ended (nearly 20 years ago), the project has been operated as a purely volunteer effort. Anyone wishing to assist in these efforts should send an email to Robbins.

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With the development of methods for adding typeset side notes to PDF files, the ESP project now plans to add annotated versions of some classical papers to its holdings. We also plan to add new reference and pedagogical material. We have already started providing regularly updated, comprehensive bibliographies to the ESP.ORG site.

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