Proteome Analysis of the Surface of Trichomonas vaginalis Reveals Novel Proteins and Strain-dependent Differential Expression

Abstract

The identification of surface proteins on the plasma membrane of pathogens is of fundamental importance in understanding host-pathogen interactions. Surface proteins of the extracellular parasite Trichomonas are implicated in the initial adherence to mucosal tissue and are likely to play a critical role in the long term survival of this pathogen in the urogenital tract. In this study, we used cell surface biotinylation and multidimensional protein identification technology to identify the surface proteome of six strains of Trichomonas vaginalis with differing adherence capacities to vaginal epithelial cells. A combined total of 411 proteins were identified, and of these, 11 were found to be more abundant in adherent strains relative to less adherent parasites. The mRNA levels of five differentially expressed proteins selected for quantitative RT-PCR analysis mirrored their observed protein levels, confirming their up-regulation in highly adherent strains. As proof of principle and to investigate a possible role in pathogenesis for differentially expressed proteins, gain of function experiments were performed using two novel proteins that were among the most highly expressed surface proteins in adherent strains. Overexpression of either of these proteins, TVAG_244130 or TVAG_166850, in a relatively non-adherent strain increased attachment of transfected parasites to vaginal epithelial cells ϳ2.2-fold. These data support a role in adhesion for these abundant surface proteins. Our analyses demonstrate that comprehensive profiling of the cell surface proteome of different parasite strains is an effective approach to identify potential new adhesion factors as well as other surface molecules that may participate in establishing and maintaining infection by this extracellular pathogen. Molecular & Cellular Proteomics 9:1554 -1566, 2010.

Trichomonas vaginalis Contact-Dependent Cytolysis of Epithelial Cells

“…Instead, it adheres to host urogenital epithelium (31). Currently, only three T. vaginalis surface molecules have been shown to play a role in attachment of the parasite to host epithelial cells: an abundant lipoglycan called TvLG (32,33,34) and two related hypothetical proteins (35). Several other candidate proteins are also under investigation (36,37).…”

Rho GTPases as pathogen targets: Focus on curable sexually transmitted infections

“…In fact, a major up-regulation of actin and actinassociated genes is evident, suggesting a role for the cytoskeleton in the amoeboid transition. 95 Interestingly, TvRsp, a Rac1 homolog gene, has been found in T. vaginalis. 96 The relationship between the Rac-related genes of this protozoan and actin cytoskeleton rearrangements remains to be further explored (Fig.…”

The Glycolytic Enzyme Triosephosphate Isomerase of Trichomonas vaginalis Is a Surface-Associated Protein Induced by Glucose That Functions as a Laminin- and Fibronectin-Binding Protein

“…Recently, the TIM protein was also identified in the surface proteome of E. histolytica (49) and in the cell wall proteome of C. albicans (50); however, the specific surface function of TIM in E. histolytica has not been described yet. Similar strategies have been used to determine the proteome of T. vaginalis surface; however, TvTIM proteins were not identified (59).…”