Background Few, if any, protozoan parasites are reported to exhibit extreme organ tropism like the flagellate In cattle, infects the reproductive system causing abortion, whereas the infection in cats results in chronic large bowel diarrhoea. Orthologs formed a large proportion of highly expressed transcripts in both genotypes (bovine genotype: 76%, feline genotype: 56%). Mining the libraries for protease virulence factors revealed the cysteine proteases (CP) to be the most common. In total, 483 and 445 bovine and feline transcripts were identified as putative proteases based on MEROPS database, with 9 hits to putative protease inhibitors. In bovine CP8 is the preferentially transcribed CP while in the feline genotype, transcription of CP7 showed higher abundance. druggability analysis of the two genotypes revealed that when host sequences are taken into account, drug targets are genotype-specific. Conclusion Gene discovery analysis based on RNA-seq data analysis revealed prominent similarities between the bovine and feline suggesting recent adaptation to their respective host/niche. represents a unique case of a mammalian protozoan expanding its parasitic grasp across distantly related host lineages. Consequences of the host-range for drug GSK1363089 targeting are uncovered here, demonstrating that targets of the parasite GSK1363089 in one host are not necessarily ideal for the same parasite in another host. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-955) contains supplementary material, which is available to authorized users. Background The protozoan flagellate belongs to the phylum Parabasalia, which includes the human parasite; Originally described as a nasal and gastrointestinal commensal of pigs, infects the urogenital tract of cattle resulting in disease known as trichomoniasis [2C4]. Transmission of the Rabbit Polyclonal to CYSLTR1 disease to female cows occurs during coitus with infected bulls, which can result in abortion of the foetus [5C8]. Recently, has been identified as the etiological agent of gastrointestinal contamination of domestic cats, where contamination results in chronic large bowel diarrhoea [9C11]. The disease in both hosts is very difficult to treat. Bovine trichomoniasis is currently untreatable and the only control measure available to farmers is usually to cull infected bulls or remove them from the breeding herd. Although treatment options for feline trichomoniasis do exist, they are becoming increasingly ineffective due to evolving parasite drug resistance and issues associated with host drug toxicity [12C14]. represents an intriguing model to study host-parasite interactions. There has been much conjecture as to the origins of the bovine and feline isolates. In particular, are they different parasites or merely closely related genotypes? Given that both infections are caused by it is not surprising that historically they have been assumed to be the same parasite. The adaptation of parasites to different hosts is usually nothing new, however, the extreme host-organ tropism of the bovine isolate (vagina) and feline isolate (gastrointestinal tract) suggest that they are distinct genotypes that, over the course of their respective evolutions, have preferentially adapted to their respective host/niche [4, 15]. Further evidence as to their distinctiveness (albeit limited) has been exhibited experimentally when the bovine genotype is usually introduced into the feline intestinal tract, and vice versa. Although both genotypes are capable of establishing contamination in their nontypical host, the pathology is usually markedly less than on their preferred hosts [10, 16]. Successful delineation of the genotypes would enable a more precise estimation of trichomonas species richness and permit a better epidemiological understanding of the pathological basis of these diseases. Currently, artificial insemination and culling of infected animals ensures that a low contamination level is usually maintained in intensively-managed cattle industries [17, 18]. Infections, however, are still prevalent in extensive farming systems [17, 18]. Moreover, current evaluation of the contamination in domestic cats indicated a high prevalence, especially in young (6C12 month old) pedigree catteries [19]. Although it has recently GSK1363089 been established.