title: Functional organization of a multimodular bacterial chemosensory apparatus.
abstract: Chemosensory systems (CSS) are complex regulatory pathways capable of perceiving external signals and translating them into different cellular behaviors such as motility and development. In the δ-proteobacterium Myxococcus xanthus, chemosensing allows groups of cells to orient themselves and aggregate into specialized multicellular biofilms termed fruiting bodies. M. xanthus contains eight predicted CSS and 21 chemoreceptors. In this work, we systematically deleted genes encoding components of each CSS and chemoreceptors and determined their effects on M. xanthus social behaviors. Then, to understand how the 21 chemoreceptors are distributed among the eight CSS, we examined their phylogenetic distribution, genomic organization and subcellular localization. We found that, in vivo, receptors belonging to the same phylogenetic group colocalize and interact with CSS components of the respective phylogenetic group. Finally, we identified a large chemosensory module formed by three interconnected CSS and multiple chemoreceptors and showed that complex behaviors such as cell group motility and biofilm formation require regulatory apparatus composed of multiple interconnected Che-like systems.
authors.affiliation: Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, CNRS-Aix-Marseille University, Marseille, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Moine
authors.affiliation: Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, CNRS-Aix-Marseille University, Marseille, France.
authors.forename: Rym
authors.initials: R
authors.lastname: Agrebi
authors.affiliation: Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, CNRS-Aix-Marseille University, Marseille, France.
authors.forename: Leon
authors.initials: L
authors.lastname: Espinosa
authors.affiliation: Department of Microbiology, University of Iowa, Iowa City, Iowa, United States of America.
authors.forename: John R
authors.initials: JR
authors.lastname: Kirby
authors.affiliation: Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, United States of America.
authors.forename: David R
authors.initials: DR
authors.lastname: Zusman
authors.affiliation: Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, CNRS-Aix-Marseille University, Marseille, France.
authors.forename: Tam
authors.initials: T
authors.lastname: Mignot
authors.affiliation: Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, CNRS-Aix-Marseille University, Marseille, France.
authors.forename: Emilia M F
authors.initials: EM
authors.lastname: Mauriello
mesh_terms: D018441:Biofilms / Q000254:growth & development; D002465:Cell Movement / Q000235:genetics; D002633:Chemotaxis / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D009068:Movement; D016941:Myxococcus xanthus / Q000737:chemistry / Q000235:genetics* / Q000254:growth & development; D010802:Phylogeny; D015398:Signal Transduction / Q000235:genetics*