Isolation and cloning of exendin precursor cDNAs from single samples of venom from the Mexican beaded lizard ( Heloderma horridum) and the Gila monster ( Heloderma suspectum)

Abstract

Reptile venoms are complex cocktails of bioactive molecules, including peptides. While the drug discovery potential of most species remains unrealized, many are endangered and afforded protection under international treaties. In this study, we describe how potential clinically important bioactive peptides and their corresponding mRNAs can be structurally characterized from single, small samples of reptile venom. The potential type-2 diabetes therapeutics, exendin-3 and exendin-4, from the Mexican beaded lizard ( Heloderma horridum) and the Gila monster ( Heloderma suspectum), respectively, have been characterized at both protein and nucleic acid levels to illustrate the efficacy of the technique and its contribution to biodiversity conservation.