Gene expression profiling of the venom gland from the Venezuelan mapanare ( Bothrops colombiensis ) using expressed sequence tags (ESTs)

Background Bothrops colombiensis is a highly dangerous pit viper and responsible for over 70 % of snakebites in Venezuela. Although the composition in B. colombiensis venom has been identified using a proteome analysis, the venom gland transcriptome is currently lacking. Results We constructed a cDNA library from the venom gland of B. colombiensis , and a set of 729 high quality expressed sequence tags (ESTs) was identified. A total number of 344 ESTs (47.2 % of total ESTs) was related to toxins. The most abundant toxin transcripts were metalloproteinases (37.5 %), phospholipases A 2 s (PLA 2 , 29.7 %), and serine proteinases (11.9 %). Minor toxin transcripts were linked to waprins (5.5 %), C-type lectins (4.1 %), ATPases (2.9 %), cysteine-rich secretory proteins (CRISP, 2.3 %), snake venom vascular endothelium growth factors (svVEGF, 2.3 %), L-amino acid oxidases (2 %), and other putative toxins (1.7 %). While 160 ESTs (22 % of total ESTs) coded for translation proteins, regulatory proteins, ribosomal proteins, elongation factors, release factors, metabolic proteins, and immune response proteins. Other proteins detected in the transcriptome (87 ESTs, 11.9 % of total ESTs) were undescribed proteins with unknown functions. The remaining 138 (18.9 %) cDNAs had no match with known GenBank accessions. Conclusion This study represents the analysis of transcript expressions and provides a physical resource of unique genes for further study of gene function and the development of novel molecules for medical applications.