title: Effector proteins support the asymmetric apportioning of Salmonella during cytokinesis.
abstract: Salmonella-infected cells are characterized by the presence of intra-cellular membranous tubules that emerge from bacterial vacuoles and extend along microtubules. The formation of Salmonella-induced tubules depends on the Salmonella pathogenicity island 2-encoded type III secretion system (T3SS-2) that translocates bacterial effector proteins inside host cells. Effector proteins have enzymatic activities or allow for hijacking of cellular functions. The role of Salmonella-induced tubules in virulence remains unclear but their absence is correlated with virulence defects. This study describes the presence of inter-cellular tubules that arise between daughter cells during cytokinesis. Inter-cellular tubules connect bacterial vacuoles originally present in the parent cell and that have been apportioned between daughters. Their formation requires a functional T3SS-2 and effector proteins. Our data establish a correlation between the formation of inter-cellular tubules and the asymmetric distribution of bacterial vacuoles in daughters. Thus, by manipulating the distribution of bacteria in cytokinetic cells, Salmonella T3SS-2 effector proteins may increase bacterial spreading and the systemic character of the infection.
authors.affiliation: a Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2 , Inserm, U1104, CNRS UMR7280, Marseille , France.
authors.forename: Yaya
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: a Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2 , Inserm, U1104, CNRS UMR7280, Marseille , France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Gorvel
authors.affiliation: a Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2 , Inserm, U1104, CNRS UMR7280, Marseille , France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Méresse
mesh_terms: D001426:Bacterial Proteins / Q000502:physiology*; D002453:Cell Cycle; D048749:Cytokinesis; D044404:Genomic Islands; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D012486:Salmonella typhimurium / Q000166:cytology* / Q000502:physiology* / Q000648:ultrastructure; D000069296:Type III Secretion Systems / Q000235:genetics / Q000378:metabolism*; D014617:Vacuoles; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D000069296:Type III Secretion Systems; D037521:Virulence Factors
keywords: Salmonella; effector protein; eukaryotic cell cycle; type 3 secretion system; virulence