scholarly journals The Myxococcus xanthus Nla4 Protein Is Important for Expression of Stringent Response-Associated Genes, ppGpp Accumulation, and Fruiting Body Development

2007 ◽  
Vol 189 (23) ◽  
pp. 8474-8483 ◽  
Author(s):  
Faisury Ossa ◽  
Michelle E. Diodati ◽  
Nora B. Caberoy ◽  
Krista M. Giglio ◽  
Mick Edmonds ◽  
...  
Keyword(s):  
Fruiting Body ◽  
Expression Patterns ◽  
Myxococcus Xanthus ◽  
Stringent Response ◽  
Fruiting Body Formation ◽  
Body Development ◽  
Normal Expression ◽  
Fruiting Body Development ◽  
Coordinated Expression ◽  
Low Levels

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.

scholarly journals Multicellular Development in Myxococcus xanthus Is Stimulated by Predator-Prey Interactions

2007 ◽  
Vol 189 (15) ◽  
pp. 5675-5682 ◽  
Author(s):  
James E. Berleman ◽  
John R. Kirby
Keyword(s):  
Fruiting Body ◽  
Prey Availability ◽  
Process Analysis ◽  
Myxococcus Xanthus ◽  
Stringent Response ◽  
Fruiting Bodies ◽  
Fruiting Body Formation ◽  
Multicellular Development ◽  
Body Formation ◽  
Body Development

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.

scholarly journals New Locus Important for Myxococcus Social Motility and Development

2007 ◽  
Vol 189 (21) ◽  
pp. 7937-7941 ◽  
Author(s):  
Cui-ying Zhang ◽  
Ke Cai ◽  
Hong Liu ◽  
Yong Zhang ◽  
Hong-wei Pan ◽  
...  
Keyword(s):  
Fruiting Body ◽  
Myxococcus Xanthus ◽  
Gliding Motility ◽  
Salt Tolerant ◽  
Fruiting Body Formation ◽  
Body Formation ◽  
Homologous Genes ◽  
Body Development ◽  
Fruiting Body Development ◽  
Social Motility

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.

scholarly journals SdeK Is Required for Early Fruiting Body Development in Myxococcus xanthus

1998 ◽  
Vol 180 (17) ◽  
pp. 4628-4637 ◽  
Author(s):  
Anthony G. Garza ◽  
Jeffrey S. Pollack ◽  
Baruch Z. Harris ◽  
Albert Lee ◽  
Ingrid M. Keseler ◽  
...  
Keyword(s):  
Dna Sequence ◽  
Fruiting Body ◽  
Developmental Process ◽  
Transcriptional Start Site ◽  
Expression Patterns ◽  
Myxococcus Xanthus ◽  
Predicted Amino Acid Sequence ◽  
Developmental Program ◽  
Body Development ◽  
Fruiting Body Development

ABSTRACT Myxococcus xanthus cells carrying the Ω4408 Tn5lac insertion at the sde locus show defects in fruiting body development and sporulation. Our analysis ofsde expression patterns showed that this locus is induced early in the developmental program (0 to 2 h) and that expression increases approximately fivefold after 12 h of development. Further studies showed that expression of sde is induced as growing cells enter stationary phase, suggesting that activation of thesde locus is not limited to the developmental process. Because the peak levels of sde expression in both ansde + and an sde mutant background were similar, we conclude that the sde locus is not autoregulated. Characterization of the sde locus by DNA sequence analysis indicated that the Ω4408 insertion occurred within the sdeK gene. Primer extension analyses localized the 5′ end of sde transcript to a guanine nucleotide 307 bp upstream of the proposed start for the SdeK coding sequence. The DNA sequence in the −12 and −24 regions upstream of the sdetranscriptional start site shows similarity to the ς54family of promoters. The results of complementation studies suggest that the defects in development and sporulation caused by the Ω4408 insertion are due to an inactivation of sdeK. The predicted amino acid sequence of SdeK was found to have similarity to the sequences of the histidine protein kinases of two-component regulatory systems. Based on our results, we propose that SdeK may be part of a signal transduction pathway required for the activation and propagation of the early developmental program.

scholarly journals Nla18, a Key Regulatory Protein Required for Normal Growth and Development of Myxococcus xanthus

2006 ◽  
Vol 188 (5) ◽  
pp. 1733-1743 ◽  
Author(s):  
Michelle E. Diodati ◽  
Faisury Ossa ◽  
Nora B. Caberoy ◽  
Ivy R. Jose ◽  
Wataru Hiraiwa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Regulation ◽  
Fruiting Body ◽  
Vegetative Growth ◽  
Growth And Development ◽  
Expression Patterns ◽  
Myxococcus Xanthus ◽  
Body Development ◽  
Fruiting Body Development ◽  
Mutant Cells

ABSTRACT NtrC-like activators regulate the transcription of a wide variety of adaptive genes in bacteria. Previously, we demonstrated that a mutation in the ntrC-like activator gene nla18 causes defects in fruiting body development in Myxococcus xanthus. In this report, we describe the effect that nla18 inactivation has on gene expression patterns during development and vegetative growth. Gene expression in nla18 mutant cells is altered in the early stages of fruiting body development. Furthermore, nla18 mutant cells are defective for two of the earliest events in development, production of the intracellular starvation signal ppGpp and production of A-signal. Taken together, these results indicate that the developmental program in nla18 mutant cells goes awry very early. Inactivation of nla18 also causes a dramatic decrease in the vegetative growth rate of M. xanthus cells. DNA microarray analysis revealed that the vegetative expression patterns of more than 700 genes are altered in nla18 mutant cells. Genes coding for putative membrane and membrane-associated proteins are among the largest classes of genes whose expression is altered by nla18 inactivation. This result is supported by our findings that the profiles of membrane proteins isolated from vegetative nla18 mutant and wild-type cells are noticeably different. In addition to genes that code for putative membrane proteins, nla18 inactivation affects the expression of many genes that are likely to be important for protein synthesis and gene regulation. Our data are consistent with a model in which Nla18 controls vegetative growth and development by activating the expression of genes involved in gene regulation, translation, and membrane structure.

scholarly journals Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes

2021 ◽  
Author(s):  
Laszlo G Nagy ◽  
Peter Jan Vonk ◽  
Markus Kunzler ◽  
Csenge Foldi ◽  
Mate Viragh ◽  
...  
Keyword(s):  
Cell Wall ◽  
Fruiting Body ◽  
Expression Patterns ◽  
Schizophyllum Commune ◽  
Gene Families ◽  
Second Phase ◽  
Fruiting Bodies ◽  
Body Development ◽  
Fruiting Body Development

Fruiting bodies of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates tissue differentiation, growth and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim to comprehensively identify conserved genes related to fruiting body morphogenesis and distill novel functional hypotheses for functionally poorly characterized genes. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide informed hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defense, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10% of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Key words: functional annotation; comparative genomics; cell wall remodeling; development; fruiting body morphogenesis; mushroom; transcriptome

scholarly journals Comparative Genomics and Transcriptomics To Analyze Fruiting Body Development in Filamentous Ascomycetes

Genetics ◽  
2019 ◽  
Vol 213 (4) ◽  
pp. 1545-1563 ◽  
Author(s):  
Ramona Lütkenhaus ◽  
Stefanie Traeger ◽  
Jan Breuer ◽  
Laia Carreté ◽  
Alan Kuo ◽  
...  
Keyword(s):  
Gene Expression ◽  
Fruiting Body ◽  
Molecular Mechanisms ◽  
Expression Patterns ◽  
Regulation Of Gene Expression ◽  
Comparative Transcriptomics ◽  
Fruiting Bodies ◽  
Body Development ◽  
Fruiting Body Development ◽  
Genes Encoding

Many filamentous ascomycetes develop three-dimensional fruiting bodies for production and dispersal of sexual spores. Fruiting bodies are among the most complex structures differentiated by ascomycetes; however, the molecular mechanisms underlying this process are insufficiently understood. Previous comparative transcriptomics analyses of fruiting body development in different ascomycetes suggested that there might be a core set of genes that are transcriptionally regulated in a similar manner across species. Conserved patterns of gene expression can be indicative of functional relevance, and therefore such a set of genes might constitute promising candidates for functional analyses. In this study, we have sequenced the genome of the Pezizomycete Ascodesmis nigricans, and performed comparative transcriptomics of developing fruiting bodies of this fungus, the Pezizomycete Pyronema confluens, and the Sordariomycete Sordaria macrospora. With only 27 Mb, the A. nigricans genome is the smallest Pezizomycete genome sequenced to date. Comparative transcriptomics indicated that gene expression patterns in developing fruiting bodies of the three species are more similar to each other than to nonsexual hyphae of the same species. An analysis of 83 genes that are upregulated only during fruiting body development in all three species revealed 23 genes encoding proteins with predicted roles in vesicle transport, the endomembrane system, or transport across membranes, and 13 genes encoding proteins with predicted roles in chromatin organization or the regulation of gene expression. Among four genes chosen for functional analysis by deletion in S. macrospora, three were shown to be involved in fruiting body formation, including two predicted chromatin modifier genes.

scholarly journals Transcript Profiling Reveals Novel Marker Genes Involved in Fruiting Body Formation in Tuber borchii

2005 ◽  
Vol 4 (9) ◽  
pp. 1599-1602 ◽  
Author(s):  
Silvia Gabella ◽  
Simona Abbà ◽  
Sebastien Duplessis ◽  
Barbara Montanini ◽  
Francis Martin ◽  
...  
Keyword(s):  
Fruiting Body ◽  
Marker Genes ◽  
Fruiting Bodies ◽  
Fruiting Body Formation ◽  
Tuber Borchii ◽  
Body Formation ◽  
Physiological Processes ◽  
Body Development ◽  
Fruiting Body Development ◽  
Two Stages

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.

scholarly journals β-d-Allose Inhibits Fruiting Body Formation and Sporulation in Myxococcus xanthus

2006 ◽  
Vol 189 (1) ◽  
pp. 169-178 ◽  
Author(s):  
Marielena Chavira ◽  
Nga Cao ◽  
Karen Le ◽  
Tanveer Riar ◽  
Navid Moradshahi ◽  
...  
Keyword(s):  
Fruiting Body ◽  
Myxococcus Xanthus ◽  
Fruiting Body Formation ◽  
Submerged Cultures ◽  
Multicellular Development ◽  
Body Formation ◽  
Body Development ◽  
Phenotype Microarrays ◽  
Glucose Phosphorylation ◽  
High Concentrations

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.

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