scholarly journals Social selection within aggregative multicellular development drives morphological evolution

2021 ◽  
Author(s):  
Marco La Fortezza ◽  
Gregory Jon Velicer

The evolution of developmental systems might be shaped by both historical differences in developmental features and social selection, among other factors. In aggregative multicellularity, development is itself a social process in which unicellular organisms cooperate in carrying out complex developmental programs. In some aggregative systems, development culminates in the construction of spore-packed fruiting bodies. Fruiting body development in myxobacteria often unfolds within genetically and behaviorally diverse conspecific cellular environments that can include social defection and warfare. Here we use the bacterium Myxococcus xanthus to test whether the character of the cellular environment during aggregative development shapes morphological evolution. We manipulated the cellular composition of Myxococcus development in an experiment in which evolving populations initiated from a single ancestor repeatedly co-developed with one of several non-evolving partners - a benign cooperator, one of three cheaters or one of three antagonists. Fruiting body morphology was found to diversify as a function of developmental partners, revealing adaptation specific to distinct cellular environments. Collectively, antagonistic partners selected for higher levels of robust fruiting body formation than did cheaters or the benign cooperator. Moreover, even small degrees of genetic divergence between the distinct cheater partners were sufficient to drive treatment-level morphological divergence. Co-developmental partners not only shaped mean trait evolution but also determined the magnitude and dynamics of stochastic morphological diversification and subsequent convergence. In sum, we find that even few genetic differences affecting developmental and social features can greatly impact the morphological evolution of multicellular bodies and experimentally demonstrate that microbial warfare can promote cooperation.

2021 ◽  
Vol 288 (1963) ◽  
Author(s):  
Marco La Fortezza ◽  
Gregory J. Velicer

Aggregative multicellular development is a social process involving complex forms of cooperation among unicellular organisms. In some aggregative systems, development culminates in the construction of spore-packed fruiting bodies and often unfolds within genetically and behaviourally diverse conspecific cellular environments. Here, we use the bacterium Myxococcus xanthus to test whether the character of the cellular environment during aggregative development shapes its morphological evolution. We manipulated the cellular composition of Myxococcus development in an experiment in which evolving populations initiated from a single ancestor repeatedly co-developed with one of several non-evolving partners—a cooperator, three cheaters and three antagonists. Fruiting body morphology was found to diversify not only as a function of partner genotype but more broadly as a function of partner social character, with antagonistic partners selecting for greater fruiting body formation than cheaters or the cooperator. Yet even small degrees of genetic divergence between distinct cheater partners sufficed to drive treatment-level morphological divergence. Co-developmental partners also determined the magnitude and dynamics of stochastic morphological diversification and subsequent convergence. In summary, we find that even just a few genetic differences affecting developmental and social features can greatly impact morphological evolution of multicellular bodies and experimentally demonstrate that microbial warfare can promote cooperation.


2007 ◽  
Vol 189 (15) ◽  
pp. 5675-5682 ◽  
Author(s):  
James E. Berleman ◽  
John R. Kirby

ABSTRACT Myxococcus xanthus is a predatory bacterium that exhibits complex social behavior. The most pronounced behavior is the aggregation of cells into raised fruiting body structures in which cells differentiate into stress-resistant spores. In the laboratory, monocultures of M. xanthus at a very high density will reproducibly induce hundreds of randomly localized fruiting bodies when exposed to low nutrient availability and a solid surface. In this report, we analyze how M. xanthus fruiting body development proceeds in a coculture with suitable prey. Our analysis indicates that when prey bacteria are provided as a nutrient source, fruiting body aggregation is more organized, such that fruiting bodies form specifically after a step-down or loss of prey availability, whereas a step-up in prey availability inhibits fruiting body formation. This localization of aggregates occurs independently of the basal nutrient levels tested, indicating that starvation is not required for this process. Analysis of early developmental signaling relA and asgD mutants indicates that they are capable of forming fruiting body aggregates in the presence of prey, demonstrating that the stringent response and A-signal production are surprisingly not required for the initiation of fruiting behavior. However, these strains are still defective in differentiating to spores. We conclude that fruiting body formation does not occur exclusively in response to starvation and propose an alternative model in which multicellular development is driven by the interactions between M. xanthus cells and their cognate prey.


2006 ◽  
Vol 189 (1) ◽  
pp. 169-178 ◽  
Author(s):  
Marielena Chavira ◽  
Nga Cao ◽  
Karen Le ◽  
Tanveer Riar ◽  
Navid Moradshahi ◽  
...  

ABSTRACT Myxococcus xanthus, a gram-negative soil bacterium, responds to amino acid starvation by entering a process of multicellular development which culminates in the assembly of spore-filled fruiting bodies. Previous studies utilizing developmental inhibitors (such as methionine, lysine, or threonine) have revealed important clues about the mechanisms involved in fruiting body formation. We used Biolog phenotype microarrays to screen 384 chemicals for complete inhibition of fruiting body development in M. xanthus. Here, we report the identification of a novel inhibitor of fruiting body formation and sporulation, β-d-allose. β-d-Allose, a rare sugar, is a member of the aldohexose family and a C3 epimer of glucose. Our studies show that β-d-allose does not affect cell growth, viability, agglutination, or motility. However, β-galactosidase reporters demonstrate that genes activated between 4 and 14 h of development show significantly lower expression levels in the presence of β-d-allose. Furthermore, inhibition of fruiting body formation occurs only when β-d-allose is added to submerged cultures before 12 h of development. In competition studies, high concentrations of galactose and xylose antagonize the nonfruiting response to β-d-allose, while glucose is capable of partial antagonism. Finally, a magellan-4 transposon mutagenesis screen identified glcK, a putative glucokinase gene, required for β-d-allose-mediated inhibition of fruiting body formation. Subsequent glucokinase activity assays of the glcK mutant further supported the role of this protein in glucose phosphorylation.


2007 ◽  
Vol 189 (21) ◽  
pp. 7937-7941 ◽  
Author(s):  
Cui-ying Zhang ◽  
Ke Cai ◽  
Hong Liu ◽  
Yong Zhang ◽  
Hong-wei Pan ◽  
...  

ABSTRACT The mts locus in salt-tolerant Myxococcus fulvus HW-1 was found to be critical for gliding motility, fruiting-body formation, and sporulation. The homologous genes in Myxococcus xanthus are also important for social motility and fruiting-body development. The mts genes were determined to be involved in cell-cell cohesion in both myxobacterial species.


2005 ◽  
Vol 4 (9) ◽  
pp. 1599-1602 ◽  
Author(s):  
Silvia Gabella ◽  
Simona Abbà ◽  
Sebastien Duplessis ◽  
Barbara Montanini ◽  
Francis Martin ◽  
...  

ABSTRACT cDNA arrays were used to explore mechanisms controlling fruiting body development in the truffle Tuber borchii. Differences in gene expression were higher between reproductive and vegetative stage than between two stages of fruiting body maturation. We suggest hypotheses about the importance of various physiological processes during the development of fruiting bodies.


2007 ◽  
Vol 189 (23) ◽  
pp. 8474-8483 ◽  
Author(s):  
Faisury Ossa ◽  
Michelle E. Diodati ◽  
Nora B. Caberoy ◽  
Krista M. Giglio ◽  
Mick Edmonds ◽  
...  

ABSTRACT Changes in gene expression are important for the landmark morphological events that occur during Myxococcus xanthus fruiting body development. Enhancer binding proteins (EBPs), which are transcriptional activators, play prominent roles in the coordinated expression of developmental genes. A mutation in the EBP gene nla4 affects the timing of fruiting body formation, the morphology of mature fruiting bodies, and the efficiency of sporulation. In this study, we showed that the nla4 mutant accumulates relatively low levels of the stringent nucleotide ppGpp. We also found that the nla4 mutant is defective for early developmental events and for vegetative growth, phenotypes that are consistent with a deficiency in ppGpp accumulation. Further studies revealed that nla4 cells produce relatively low levels of GTP, a precursor of RelA-dependent synthesis of (p)ppGpp. In addition, the normal expression patterns of all stringent response-associated genes tested, including the M. xanthus ppGpp synthetase gene relA, are altered in nla4 mutant cells. These findings indicate that Nla4 is part of regulatory pathway that is important for mounting a stringent response and for initiating fruiting body development.


2018 ◽  
Author(s):  
Kathy PoLam Chan ◽  
Jinhui Chang ◽  
Yichun Xie ◽  
Man Kit Cheung ◽  
Ka Lee Ma ◽  
...  

The functions of glycogen synthase kinase 3 (GSK3) have been well-studied in animal, plant and yeast. However, information on its roles in basidiomycetous fungi is still limited. In this study, we used the model mushroom Coprinopsis cinerea to study the characteristics of GSK3 in fruiting body development. Application of a GSK3 inhibitor Lithium chloride (LiCl) induced enhanced mycelial growth and inhibited fruiting body formation in C. cinerea. RNA-Seq of LiCl-treated C. cinerea resulted in a total of 14128 unigenes. There were 1210 differentially expressed genes (DEGs) between the LiCl-treated samples and control samples in the mycelium stage (first time point), whereas 1402 DEGs were detected at the stage when the control samples formed hyphal knots and the treatment samples were still in mycelium (second time point). Kyoto Encyclopedia of Genes and Genome (KEGG) pathway enrichment analysis of the DEGs revealed significant associations between the enhanced mycelium growth in LiCl treated C. cinerea and metabolism pathways such as “biosynthesis of secondary metabolite” and “biosynthesis of antibiotics”. In addition, DEGs involved in cellular process pathways, including “cell cycle-yeast” and “meiosis-yeast”, were identified in C. cinerea fruiting body formation suppressed by LiCl under favorable environmental conditions. Our findings suggest that GSK3 activity is essential for fruiting body formation as it affects the expression of fruiting body induction genes and genes in cellular processes. Further functional studies of GSK3 in basidiomycetous fungi may help understand the relationships between environmental signals and fruiting body development.


2007 ◽  
Vol 189 (24) ◽  
pp. 9126-9130 ◽  
Author(s):  
Patrick D. Curtis ◽  
Rion G. Taylor ◽  
Roy D. Welch ◽  
Lawrence J. Shimkets

ABSTRACT Microcinematography was used to examine fruiting body development of Myxococcus xanthus. Wild-type cells progress through three distinct phases: a quiescent phase with some motility but little aggregation (0 to 8 h), a period of vigorous motility leading to raised fruiting bodies (8 to 16 h), and a period of maturation during which sporulation is initiated (16 to 48 h). Fruiting bodies are extended vertically in a series of tiers, each involving the addition of a cell monolayer on top of the uppermost layer. A pilA (MXAN_5783) mutant produced less extracellular matrix material and thus allowed closer examination of tiered aggregate formation. A csgA (MXAN_1294) mutant exhibited no quiescent phase, aberrant aggregation in phase 2, and disintegration of the fruiting bodies in the third phase.


Author(s):  
Foziya Khan ◽  
Ramesh Chandra

Objective: Fungi are heterotrophs and are involved in decomposition, nutrient cycling and nutrient transport, and are indispensable for achieving sustainable development. Mushrooms are the fungi with a distinctive fruiting body. Mushrooms are produced all over the world. In India, Punjab is the leading mushroom growing state. Mushrooms are rich sources of proteins, vitamins and minerals. Different types of immunoceuticals like lentinan, schizophyllan, active hexose correlated compound (AHCC) etc. have also been prepared from various mushrooms. The present review work highlights important observations in the area of mushroom. Methods: This review also shows that how several factors affect the fruiting body formation of mushrooms, which includes physiological (composition of culture media) and environmental factors (light, temperature, salinity, etc.). There are different factors like light, temperature etc. which affects the fruiting body development.Results: It has been found that, light has positive effects on hyphal aggregation and fruiting body maturation. It has been found that in oyster mushroom, light is essential for both normal expansion of pileus and in spore formation. It has been found that length of Stipe and the diameter of cap decreases with an increase in the concentration of CO2. Also, there is a range of temperature within which sporophore development occurs. The composition of media affects the growth of mushrooms too. It’s important to maintain a balance between carbon and nitrogen sources for induction of the fruiting body.Conclusion: There are different environmental factors affecting the fruiting body development of mushrooms. Hence, by adjusting various factors like temperature, light, media composition production of mushrooms can be increased.


Genetics ◽  
1997 ◽  
Vol 147 (2) ◽  
pp. 567-580 ◽  
Author(s):  
Stefanie Pöggeler ◽  
Siegfried Risch ◽  
Ulrich Kück ◽  
Heinz D Osiewacz

Homokaryons from the homothallic ascomycte Sordaria macrospora are able to enter the sexual pathway and to form fertile fruiting bodies. To analyze the molecular basis of homothallism and to elucidate the role of mating-products during fruiting body development, we cloned and sequenced the entire S. macrospora mating-type locus. Comparison of the Sordaria mating-type locus with mating-type idiomorphs from the heterothallic ascomycetes Neurospora crassa and Podospora anserina revealed that sequences from both idiomorphs (A/a and mat–/mat+, respectively) are contiguous in S. macrospora. DNA sequencing of the S. macrospora mating-type region allowed the identification of four open reading frames (ORFs), which were termed Smt-a1, SmtA-1, SmtA-2 and SmtA-3. While Smt-a1, SmtA-1, and SmtA-2 show strong sequence similarities with the corresponding N. crassa mating-type ORFs, SmtA-3 has a chimeric character. It comprises sequences that are similar to the A and a mating-type idiomorph from N. crassa. To determine functionality of the S. macrospora mating-type genes, we show that all ORFs are transcriptionally expressed. Furthermore, we transformed the S. macrospora mating-type genes into mat– and mat+ strains of the closely related heterothallic fungus P. anserina. The transformation experiments show that mating-type genes from S. macrospora induce fruiting body formation in P. anserina.


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