title: The small G-protein MglA connects to the MreB actin cytoskeleton at bacterial focal adhesions.
abstract: In Myxococcus xanthus the gliding motility machinery is assembled at the leading cell pole to form focal adhesions, translocated rearward to propel the cell, and disassembled at the lagging pole. We show that MglA, a Ras-like small G-protein, is an integral part of this machinery. In this function, MglA stimulates the assembly of the motility complex by directly connecting it to the MreB actin cytoskeleton. Because the nucleotide state of MglA is regulated spatially and MglA only binds MreB in the guanosine triphosphate-bound form, the motility complexes are assembled at the leading pole and dispersed at the lagging pole where the guanosine triphosphatase activating protein MglB disrupts the MglA-MreB interaction. Thus, MglA acts as a nucleotide-dependent molecular switch to regulate the motility machinery spatially. The function of MreB in motility is independent of its function in peptidoglycan synthesis, representing a coopted function. Our findings highlight a new function for the MreB cytoskeleton and suggest that G-protein-cytoskeleton interactions are a universally conserved feature.
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Treuner-Lange
authors.affiliation: Institut de Pharmacologie Moléculaire et Cellulaire, UMR 7275 Centre National de la Recherche Scientifique, Université de Nice Sophia Antipolis, 06560 Valbonne, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Macia
authors.affiliation: Laboratoire de Chimie Bactérienne, UMR 7283 Centre National de la Recherche Scientifique, Aix Marseille University, 13009 Marseille, France.
authors.forename: Mathilde
authors.initials: M
authors.lastname: Guzzo
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany.
authors.forename: Edina
authors.initials: E
authors.lastname: Hot
authors.affiliation: Laboratoire de Chimie Bactérienne, UMR 7283 Centre National de la Recherche Scientifique, Aix Marseille University, 13009 Marseille, France.
authors.forename: Laura M
authors.initials: LM
authors.lastname: Faure
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany.
authors.forename: Beata
authors.initials: B
authors.lastname: Jakobczak
authors.affiliation: Laboratoire de Chimie Bactérienne, UMR 7283 Centre National de la Recherche Scientifique, Aix Marseille University, 13009 Marseille, France.
authors.forename: Leon
authors.initials: L
authors.lastname: Espinosa
authors.affiliation: Institut de Pharmacologie Moléculaire et Cellulaire, UMR 7275 Centre National de la Recherche Scientifique, Université de Nice Sophia Antipolis, 06560 Valbonne, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Alcor
authors.affiliation: Laboratoire de Chimie Bactérienne, UMR 7283 Centre National de la Recherche Scientifique, Aix Marseille University, 13009 Marseille, France.
authors.forename: Adrien
authors.initials: A
authors.lastname: Ducret
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Keilberg
authors.affiliation: Laboratoire de Chimie Bactérienne, UMR 7283 Centre National de la Recherche Scientifique, Aix Marseille University, 13009 Marseille, France.
authors.forename: Jean Philippe
authors.initials: JP
authors.lastname: Castaing
authors.affiliation: Centre Commun de Microscopie Appliquée, Université de Nice Sophia Antipolis, 06103 Nice, France.
authors.forename: Sandra
authors.initials: S
authors.lastname: Lacas Gervais
authors.affiliation: Institut de Pharmacologie Moléculaire et Cellulaire, UMR 7275 Centre National de la Recherche Scientifique, Université de Nice Sophia Antipolis, 06560 Valbonne, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Franco
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany franco@ipmc.cnrs.fr sogaard@mpi-marburg.mpg.de tmignot@imm.cnrs.fr.
authors.forename: Lotte
authors.initials: L
authors.lastname: Søgaard-Andersen
authors.affiliation: Laboratoire de Chimie Bactérienne, UMR 7283 Centre National de la Recherche Scientifique, Aix Marseille University, 13009 Marseille, France franco@ipmc.cnrs.fr sogaard@mpi-marburg.mpg.de tmignot@imm.cnrs.fr.
authors.forename: Tâm
authors.initials: T
authors.lastname: Mignot
mesh_terms: D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D022001:Focal Adhesions / Q000378:metabolism; D016941:Myxococcus xanthus / Q000166:cytology / Q000378:metabolism*; D010457:Peptidoglycan / Q000096:biosynthesis; D011485:Protein Binding; D025941:Protein Interaction Mapping; D021381:Protein Transport
chemical_list: D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; D010457:Peptidoglycan; C071728:MglA protein, Myxococcus xanthus