HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 279, Issue 46, 47792-47798, November 12, 2004

This Article Full Text Full Text (PDF) All Versions of this Article: 279/46/47792    most recent M406824200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by van der Goot, F. G. Articles by Lafont, F. Search for Related Content PubMed PubMed Citation Articles by van der Goot, F. G. Articles by Lafont, F. Social Bookmarking                      What's this?

Rafts Can Trigger Contact-mediated Secretion of Bacterial Effectors via a Lipid-based Mechanism^*

Françoise G. van der Goot, Guy Tran van Nhieu, Abdelmounaaïm Allaoui¶, Phillipe Sansonetti, and Frank Lafont||

From the Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH1211 Genève 4, Switzerland, Unité de Pathogénie Microbienne Moléculaire, INSERM U389, Institut Pasteur, 28 rue du Dr. Roux, F-75724 Paris cedex 15, France, and ^¶Laboratoire de Bactériologie Moléculaire, Faculté de Médecine, Université Libre de Bruxelles, 1070 Brussels, Belgium

Infection by the Gram-negative bacterial pathogen Shigella flexneri depends on its ability to invade host cells. Bacterial engulfment requires a functional type III secretion system (TTSS) allowing the translocation into host cells of bacterial effectors that activate cell-signaling cascades. We demonstrated previously that specialized lipid membrane domains enriched in cholesterol and sphingolipids (rafts) are involved during early steps of invasion, namely in binding and host cell entry. In this study, we addressed the issue of contact-mediated secretion by the TTSS. We show that contact-mediated and TTSS-induced hemolysis depend on the presence of cholesterol on the host cell surface. We found that purified detergent resistant membranes were able to activate TTSS. Finally, we found that artificial liposomes, devoid of proteins, were able to activate the TTSS but only when their composition mimicked that of lipid rafts. Altogether, these data indicate that specific lipid packing can trigger contact-mediated secretion by S. flexneri.

Received for publication, June 18, 2004 , and in revised form, August 18, 2004.

^* This work was supported by a grant from the Swiss National Science Foundation and the EMBO Young Investigator Program (to F. G. v. d. G.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

^|| To whom correspondence should be addressed. Tel.: 41-22-379-5656; Fax: 41-22-379-5896; E-mail: Frank.Lafont{at}medecine.unige.ch.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				G. N. Schroeder and H. Hilbi Molecular Pathogenesis of Shigella spp.: Controlling Host Cell Signaling, Invasion, and Death by Type III Secretion Clin. Microbiol. Rev., January 1, 2008; 21(1): 134 - 156. [Abstract] [Full Text] [PDF]

				G. N. Schroeder, N. J. Jann, and H. Hilbi Intracellular type III secretion by cytoplasmic Shigella flexneri promotes caspase-1-dependent macrophage cell death Microbiology, September 1, 2007; 153(9): 2862 - 2876. [Abstract] [Full Text] [PDF]

				A. J. Olive, R. Kenjale, M. Espina, D. S. Moore, W. L. Picking, and W. D. Picking Bile Salts Stimulate Recruitment of IpaB to the Shigella flexneri Surface, Where It Colocalizes with IpaD at the Tip of the Type III Secretion Needle Infect. Immun., May 1, 2007; 75(5): 2626 - 2629. [Abstract] [Full Text] [PDF]

				P. R. Race, J. H. Lakey, and M. J. Banfield Insertion of the Enteropathogenic Escherichia coli Tir Virulence Protein into Membranes in Vitro J. Biol. Chem., March 24, 2006; 281(12): 7842 - 7849. [Abstract] [Full Text] [PDF]

				K. Ohya, Y. Handa, M. Ogawa, M. Suzuki, and C. Sasakawa IpgB1 Is a Novel Shigella Effector Protein Involved in Bacterial Invasion of Host Cells: ITS ACTIVITY TO PROMOTE MEMBRANE RUFFLING VIA RAC1 AND CDC42 ACTIVATION J. Biol. Chem., June 24, 2005; 280(25): 24022 - 24034. [Abstract] [Full Text] [PDF]