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

Abstract

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.

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 A₂s (PLA₂, 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.

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.