Expressed sequence tags from Eimeria brunetti--preliminary analysis and functional annotation

As a first attempt to generate sequence information from the protein-coding genes of the genomically unknown parasite, Eimeria brunetti, a cDNA library was generated from purified sporozoites in the λTriplEx2™ vector. Analysis of 283 expressed sequence tags (ESTs) from the cDNA library constructed revealed 12 contigs (26 ESTs) and 257 singletons. BLASTx analysis revealed that 50 transcripts had significant matches to known proteins, whereas the remaining 233 had no significant matches, probably representing novel genes. Based on Gene Ontology classification, the transcripts were categorized as biological process (46 ESTs), molecular function (37 ESTs), and cellular component (19 ESTs). The transcripts analyzed show maximum homology to the apicomplexan parasite Toxoplasma gondii. Despite the small number of transcripts, this is the first transcriptome analysis of E. brunetti and provides preliminary data that will increase understanding of parasite biological function.