Regulation of late-acting operons by three transcription factors and a CRISPR-Cas component during Myxococcus xanthus development.
Myxococcus
bacterial development
gene regulation
spore
Journal
Molecular microbiology
ISSN: 1365-2958
Titre abrégé: Mol Microbiol
Pays: England
ID NLM: 8712028
Informations de publication
Date de publication:
25 Mar 2024
25 Mar 2024
Historique:
revised:
06
03
2024
received:
16
10
2023
accepted:
08
03
2024
medline:
25
3
2024
pubmed:
25
3
2024
entrez:
25
3
2024
Statut:
aheadofprint
Résumé
Upon starvation, rod-shaped Myxococcus xanthus bacteria form mounds and then differentiate into round, stress-resistant spores. Little is known about the regulation of late-acting operons important for spore formation. C-signaling has been proposed to activate FruA, which binds DNA cooperatively with MrpC to stimulate transcription of developmental genes. We report that this model can explain regulation of the fadIJ operon involved in spore metabolism, but not that of the spore coat biogenesis operons exoA-I, exoL-P, and nfsA-H. Rather, a mutation in fruA increased the transcript levels from these operons early in development, suggesting negative regulation by FruA, and a mutation in mrpC affected transcript levels from each operon differently. FruA bound to all four promoter regions in vitro, but strikingly each promoter region was unique in terms of whether or not MrpC and/or the DNA-binding domain of Nla6 bound, and in terms of cooperative binding. Furthermore, the DevI component of a CRISPR-Cas system is a negative regulator of all four operons, based on transcript measurements. Our results demonstrate complex regulation of sporulation genes by three transcription factors and a CRISPR-Cas component, which we propose produces spores suited to withstand starvation and environmental insults.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Subventions
Organisme : National Science Foundation
ID : IOS-1951025
Organisme : National Science Foundation
ID : MCB-1411272
Organisme : AgBioResearch, Michigan State University
Informations de copyright
© 2024 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.
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