title: Direct modulation of the host cell cytoskeleton by Salmonella actin-binding proteins.
abstract: Invasive Salmonella trigger their own uptake into non-phagocytic eukaryotic cells by delivering virulence proteins that stimulate signaling pathways and remodel the actin cytoskeleton. It has recently emerged that Salmonella encodes two actin-binding proteins, SipC and SipA, which together efficiently nucleate actin polymerization and stabilize the resulting supramolecular filament architecture. Therefore, Salmonella might directly initiate actin polymerization independently of the cellular Arp2/3 complex early in the cell entry process. This is an unprecedented example of a direct intervention strategy to facilitate entry of a pathogen into a target cell. Here, we discuss the Salmonella actin-binding proteins and how they might function in combination with entry effectors that stimulate Rho GTPases. We propose that membrane-targeted bacterial effector proteins might trigger actin polymerization through diverse mechanisms during cell entry by bacterial pathogens.
authors.affiliation: University of Cambridge, Dept of Pathology, Tennis Court Road, CB2 1QP, Cambridge, UK. rdh24@mole.bio.cam.ac.uk
authors.forename: Richard D
authors.initials: RD
authors.lastname: Hayward
authors.forename: Vassilis
authors.initials: V
authors.lastname: Koronakis
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D051377:Actin-Related Protein 2; D000199:Actins / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism* / Q000494:pharmacology; D003598:Cytoskeletal Proteins; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D005057:Eukaryotic Cells / Q000378:metabolism; D006801:Humans; D008840:Microfilament Proteins / Q000378:metabolism / Q000494:pharmacology; D012475:Salmonella / Q000378:metabolism* / Q000472:pathogenicity; D012480:Salmonella Infections / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology
chemical_list: C495926:ACTR2 protein, human; D051377:Actin-Related Protein 2; D000199:Actins; D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; D008840:Microfilament Proteins; C094578:Salmonella invasion protein C; C118287:SipA protein, Salmonella