Functional profiling of the Tritrichomonas foetus transcriptome and proteome

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.

The most extensive transcriptome and proteome profiles were established for the first time in T. foetus, revealing potential therapeutic targets against the infection of this parasite.130Highlights► A total of 5064 ESTs were generated, representing 2674 unigenes in the T. foetus transcriptome. ► Unigenes related to potential chemotherapeutic targets and pathogenesis were identified. ► The proteome reference map for T. foetus was established and 68 highly expressed protein spots were identified. ► The datasets provided a foundation for the molecular, biochemical and functional exploration on the pathogenesis of T. foetus.