title: Cell-surface attachment of pedestal-forming enteropathogenic E. coli induces a clustering of raft components and a recruitment of annexin 2.
abstract: Annexin 2 is a Ca2+-regulated membrane- and F-actin-binding protein implicated in the stabilization or regulation of membrane/cytoskeleton contacts, or both, at the plasma membrane and at early endosomal membranes. To analyze the dynamic nature of such action we investigated whether annexin 2 could be found at sites of localized actin rearrangements occurring at the plasma membrane of HeLa cells infected with noninvading enteropathogenic Escherichia coli (EPEC). We show that adherent EPEC microcolonies, which are known to induce the formation of actin-rich pedestals beneath them, specifically recruit annexin 2 to the sites of their attachment. Mutant EPEC (EPECtir), which lack a functional receptor for intimate attachment (Tir, translocated intimin receptor) and which fail to produce full pedestal formation, are still capable of recruiting annexin 2 to the bacterial contact sites. Accumulation of annexin 2 at sites of EPEC or EPECtir attachment is accompanied by a recruitment of the annexin 2 protein ligand S100A10. EPEC and EPECtir attachment also induces a concentration of cholesterol and glycosyl phosphatidylinositol-anchored proteins at sites of bacterial contact. This indicates that membrane components present in rafts or raft-like microdomains are clustered upon EPEC adherence and that annexin 2 is recruited to the cytoplasmic membrane surface of such clusters, possibly stabilizing raft patches and their linkage to the actin cytoskeleton beneath adhering EPEC.
authors.affiliation: Institute for Medical Biochemistry, Center for Molecular Biology of Inflammation, von-Esmarch-Str. 56, D-48149 Münster, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Zobiack
authors.forename: Ursula
authors.initials: U
authors.lastname: Rescher
authors.forename: Sven
authors.initials: S
authors.lastname: Laarmann
authors.forename: Silke
authors.initials: S
authors.lastname: Michgehl
authors.forename: M Alexander
authors.initials: MA
authors.lastname: Schmidt
authors.forename: Volker
authors.initials: V
authors.lastname: Gerke
mesh_terms: D000199:Actins / Q000378:metabolism; D017306:Annexin A2 / Q000235:genetics / Q000378:metabolism*; D017209:Apoptosis; D001422:Bacterial Adhesion / Q000502:physiology*; D001426:Bacterial Proteins / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D004926:Escherichia coli / Q000472:pathogenicity* / Q000502:physiology; D029968:Escherichia coli Proteins; D005260:Female; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D021962:Membrane Microdomains / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D011485:Protein Binding; D021381:Protein Transport; D011956:Receptors, Cell Surface / Q000378:metabolism / Q000502:physiology; D009418:S100 Proteins; D014162:Transfection; D014774:Virulence; D000099248:S100 Calcium Binding Protein A10
chemical_list: D000199:Actins; D017306:Annexin A2; D001426:Bacterial Proteins; D002135:Calcium-Binding Proteins; D002784:Cholesterol; D029968:Escherichia coli Proteins; D017261:Glycosylphosphatidylinositols; D011956:Receptors, Cell Surface; D009418:S100 Proteins; D000099248:S100 Calcium Binding Protein A10; C109287:Tir protein, E coli