tailieunhanh - Báo cáo khoa học: Cytoskeleton-modulating effectors of enteropathogenic and enterohaemorrhagic Escherichia coli: Tir, EspFU and actin pedestal assembly

A variety of microbes manipulate the cytoskeleton of mammalian cells to promote their internalization, motility and⁄or spread. Among such bacte-ria, enteropathogenic Escherichia coliand enterohemorrhagic Escherichia coliare closely related pathogens that adhere to human intestinal cells and reorganize the underlying actin cytoskeleton into ‘pedestals’. | MINIREVIEW Cytoskeleton-modulating effectors of enteropathogenic and enterohaemorrhagic Escherichia coli Tir EspFU and actin pedestal assembly Kenneth G. Campellone Department of Molecular and CellBiology University of California Berkeley CA USA Keywords actin assembly Arp2 3 complex bacterial pathogenesis cell signaling EHEC EPEC EspF membrane dynamics N-WASP tyrosine kinase Correspondence K. G. Campellone Department of Molecular and CellBiology University of California Berkeley Berkeley CA 94720 USA Fax 1 510 642 8620 Tel 1 510 642 5525 E-mail campellone@ Received 27 October 2009 revised 12 February 2010 accepted 15 March 2010 doi A variety of microbes manipulate the cytoskeleton of mammalian cells to promote their internalization motility and or spread. Among such bacteria enteropathogenic Escherichia coli and enterohemorrhagic Escherichia coli are closely related pathogens that adhere to human intestinal cells and reorganize the underlying actin cytoskeleton into pedestals . The assembly of pedestals is likely to be an important step in colonization and is triggered by the E. coli virulence factors translocated intimin receptor and E. coli secreted protein F in prophage U which modulate multiple host signaling cascades that lead to actin polymerization. In recent years these bacterial effectors have been exploited as powerful experimental tools for investigating actin cytoskeletal and membrane dynamics and several studies have significantly advanced our understanding of the regulation of actin assembly in mammalian cells and the potential role of pedestal formation in pathogenesis. Introduction Numerous microbial pathogens share an ability to trigger localized actin polymerization in host cells. Such pathogens include several bacteria that invade mammalian cells gain access to the cytoplasm and stimulate actin assembly at their surface to propel them throughout the cell. The actin-based motility of several of these .