Journal of Molecular Evolution

, Volume 57, Issue 4, pp 446–452

Isolation of a Neurotoxin (α-colubritoxin) from a Nonvenomous Colubrid: Evidence for Early Origin of Venom in Snakes

Authors

    • Department of Biological Sciences, Faculty of ScienceNational University of Singapore, 119260
    • Australian Venom Research Unit, Department of PharmacologyUniversity of Melbourne, Parkville, Victoria 3010
  • Natalie G. Lumsden
    • Monash Venom Group, Department of PharmacologyMonash University, Victoria 3800
  • Wolfgang Wüster
    • School of Biological SciencesUniversity of Wales, Bangor, LL57 2UW, Wales
  • Janith C. Wickramaratna
    • Monash Venom Group, Department of PharmacologyMonash University, Victoria 3800
  • Wayne C. Hodgson
    • Monash Venom Group, Department of PharmacologyMonash University, Victoria 3800
  • R. Manjunatha Kini
    • Department of Biological Sciences, Faculty of ScienceNational University of Singapore, 119260
Article

DOI: 10.1007/s00239-003-2497-3

Cite this article as:
Fry, B.G., Lumsden, N.G., Wüster, W. et al. J Mol Evol (2003) 57: 446. doi:10.1007/s00239-003-2497-3

Abstract

The evolution of venom in advanced snakes has been a focus of long-standing interest. Here we provide the first complete amino acid sequence of a colubrid toxin, which we have called α-colubritoxin, isolated from the Asian ratsnake Coelognathusradiatus (formerly known as Elapheradiata), an archetypal nonvenomous snake as sold in pet stores. This potent postsynaptic neurotoxin displays readily reversible, competitive antagonism at the nicotinic receptor. The toxin is homologous with, and phylogenetically rooted within, the three-finger toxins, previously thought unique to elapids, suggesting that this toxin family was recruited into the chemical arsenal of advanced snakes early in their evolutionary history. LC-MS analysis of venoms from most other advanced snake lineages revealed the widespread presence of components of the same molecular weight class, suggesting the ubiquity of three-finger toxins across advanced snakes, with the exclusion of Viperidae. These results support the role of venom as a key evolutionary innovation in the early diversification of advanced snakes and provide evidence that forces a fundamental rethink of the very concept of nonvenomous snake.

Keywords

NeurotoxinVenomEvolutionMulti-geneThree fingerSnake

Copyright information

© Springer-Verlag New York Inc. 2003