title: Transcriptomic analysis of the venom gland of the red-headed krait (Bungarus flaviceps) using expressed sequence tags.
abstract: BACKGROUND
  The Red-headed krait (Bungarus flaviceps, Squamata: Serpentes: Elapidae) is a medically important venomous snake that inhabits South-East Asia. Although the venoms of most species of the snake genus Bungarus have been well characterized, a detailed compositional analysis of B. flaviceps is currently lacking.
  
  
  RESULTS
  Here, we have sequenced 845 expressed sequence tags (ESTs) from the venom gland of a B. flaviceps. Of the transcripts, 74.8% were putative toxins; 20.6% were cellular; and 4.6% were unknown. The main venom protein families identified were three-finger toxins (3FTxs), Kunitz-type serine protease inhibitors (including chain B of beta-bungarotoxin), phospholipase A2 (including chain A of beta-bungarotoxin), natriuretic peptide (NP), CRISPs, and C-type lectin.
  
  
  CONCLUSIONS
  The 3FTxs were found to be the major component of the venom (39%). We found eight groups of unique 3FTxs and most of them were different from the well-characterized 3FTxs. We found three groups of Kunitz-type serine protease inhibitors (SPIs); one group was comparable to the classical SPIs and the other two groups to chain B of beta-bungarotoxins (with or without the extra cysteine) based on sequence identity. The latter group may be functional equivalents of dendrotoxins in Bungarus venoms. The natriuretic peptide (NP) found is the first NP for any Asian elapid, and distantly related to Australian elapid NPs. Our study identifies several unique toxins in B. flaviceps venom, which may help in understanding the evolution of venom toxins and the pathophysiological symptoms induced after envenomation.
authors.affiliation: Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117546, Singapore.
authors.forename: Ang Swee
authors.initials: AS
authors.lastname: Siang
authors.forename: Robin
authors.initials: R
authors.lastname: Doley
authors.forename: Freek J
authors.initials: FJ
authors.lastname: Vonk
authors.forename: R Manjunatha
authors.initials: RM
authors.lastname: Kini
mesh_terms: D000818:Animals; D002038:Bungarotoxins / Q000032:analysis / Q000235:genetics; D017838:Bungarus / Q000235:genetics; D004546:Elapid Venoms / Q000737:chemistry / Q000235:genetics*; D020224:Expressed Sequence Tags; D020869:Gene Expression Profiling
chemical_list: D002038:Bungarotoxins; D004546:Elapid Venoms