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Tritrichomonas foetus is a potent veterinary pathogen, causing bovine and feline trichomoniasis. The principal clinical manifestation of infection in cattle is inflammation of the genital tract and infertility. In feline, the parasite causes large-bowel disease resulting in chronic diarrhea. In contrast to other well-studied protozoan, genetic data regarding the molecular characterization and expression in T. foetus is far less understood. In this study, the first large-scale T. foetus expressed sequence tag (TfEST) project was conducted on 5064 randomly selected EST clones from a non-normalized unidirectional Tf30924 cDNA library. Assembling of 5064 single-pass sequences from the 5' end resulted in 713 contigs and 1961 singlets. BLAST search revealed that 53.52% of the unigenes showed significant similarity to known sequences or protein motifs/domains. Functional classifications indicated that most of the unigenes are involved in translation, ribosomal structure and ribosome biogenesis. The average GC content of the T. foetus transcriptome is 40.93%. Intriguingly, only 31.29% of the unigenes contain the classical AAUAAA polyadenylation signal sequence at the 3'-UTR region. Furthermore, a panel of potential chemotherapeutic targets was also identified for the first time in T. foetus. The protein expression levels were verified by using two-dimensional electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. A total of 68 highly abundant protein spots were successfully identified in the reference 2-DE map based on our T. foetus-specific protein database. The EST dataset and the reference 2-DE map established in the present study will provide a foundation for future whole genome sequencing project and comparative transcriptomic/proteomic analyses to provide potential drug targets against T. foetus infection., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The morphological transformation of Trichomonas vaginalis from an ellipsoid form in batch culture to an adherent amoeboid form results from the contact of parasites with vaginal epithelial cells and with immobilized fibronectin (FN), a basement membrane component. This suggests host signaling of the parasite. We applied integrated transcriptomic and proteomic approaches to investigate the molecular responses of T. vaginalis upon binding to FN. A transcriptome analysis was performed by using large-scale expressed-sequence-tag (EST) sequencing. A total of 20,704 ESTs generated from batch culture (trophozoite-EST) versus FN-amoeboid trichomonad (FN-EST) cDNA libraries were analyzed. The FN-EST library revealed decreased amounts of transcripts that were of lower abundance in the trophozoite-EST library. There was a shift by FN-bound organisms to the expression of transcripts encoding essential proteins, possibly indicating the expression of genes for adaptation to the morphological changes needed for the FN-adhesive processes. In addition, we identified 43 differentially expressed proteins in the proteomes of FN-bound and unbound trichomonads. Among these proteins, cysteine peptidase, glyceraldehyde-3-phosphate dehydrogenase (an FN-binding protein), and stress-related proteins were upregulated in the FN-adherent cells. Stress-related genes and proteins were highly expressed in both the transcriptome and proteome of FN-bound organisms, implying that these genes and proteins may play critical roles in the response to adherence. This is the first report of a comparative proteomic and transcriptomic analysis after the binding of T. vaginalis to FN. This approach may lead to the discovery of novel virulence genes and affirm the role of genes involved in disease pathogenesis. This knowledge will permit a greater understanding of the complex host-parasite interplay.