This Article Full Text Full Text (PDF) Other Versions of this Article: IAI.01096-07v1 75/12/5669    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Swanson, K. A. Articles by Caldwell, H. D. Search for Related Content PubMed PubMed Citation Articles by Swanson, K. A. Articles by Caldwell, H. D.

 Previous Article  |  Next Article 

Infection and Immunity, December 2007, p. 5669-5677, Vol. 75, No. 12
0019-9567/07/$08.00+0     doi:10.1128/IAI.01096-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Chlamydia trachomatis Species-Specific Induction of Ezrin Tyrosine Phosphorylation Functions in Pathogen Entry

Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 58940

Received 7 August 2007/ Returned for modification 11 September 2007/ Accepted 18 September 2007

Chlamydia trachomatis is an obligate intracellular pathogen of humans that exhibits species-specific biological characteristics in its early interactions with host cells that are likely important to pathogenesis. One such characteristic is the tyrosine phosphorylation (Tyr-P) of an 70-kDa polypeptide that occurs only after infection of mammalian cells by human strains. We sought to identify this protein because of its potential significance to the pathogenesis of human chlamydial infections. Using an immunoproteomic approach we identified the host protein ezrin, a member of the ezrin-radixin-moesin (ERM) protein family that serves as a physical link between host cell receptors and the actin cytoskeleton. Confocal microscopy studies showed colocalization of ezrin and actin at the tips and crypts of microvilli, the site of chlamydial attachment and entry, respectively. To demonstrate a functional role for ezrin we infected cells with a dominant-negative (DN) ezrin phenotype or treated cells with ezrin-specific small interfering RNA (siRNA). We found that both DN and siRNA-treated cells were significantly less susceptible to infection by human chlamydial strains. Moreover, we demonstrated that inhibition of infection in ezrin DN cells occurred at the stage of chlamydial entry. We hypothesize that the C. trachomatis-specific Tyr-P of ezrin might relate to an undefined species-specific mechanism of pathogen entry that involves chlamydial specific ligand(s) and host cell coreceptor usage.

Published ahead of print on 1 October 2007.

Editor: R. P. Morrison