Fossilized Venom: The Unusually Conserved Venom Profiles of Heloderma Species (Beaded Lizards and Gila Monsters)

Toxins

Ivan Koludarov²  Timothy N. W. Jackson²  Kartik Sunagar³  Amanda Nouwens¹  Iwan Hendrikx²  Bryan G. Fry² 

[1] School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Queensland 4072, Australia; E-Mail:;Venom Evolution Lab, School of Biological Sciences, the University of Queensland, St. Lucia, Queensland 4072, Australia; E-Mails:;Department of Ecology, Evolution and Behavior, the Alexander Silberman Institute for Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel; E-Mail:

关键词: adaptive evolution;    venom;    toxin;    Heloderma;    beaded lizard;    gila monster;   

DOI  :  10.3390/toxins6123582

来源: mdpi

【 摘 要 】

Research into snake venoms has revealed extensive variation at all taxonomic levels. Lizard venoms, however, have received scant research attention in general, and no studies of intraclade variation in lizard venom composition have been attempted to date. Despite their iconic status and proven usefulness in drug design and discovery, highly venomous helodermatid lizards (gila monsters and beaded lizards) have remained neglected by toxinological research. Proteomic comparisons of venoms of three helodermatid lizards in this study has unravelled an unusual similarity in venom-composition, despite the long evolutionary time (~30 million years) separating H. suspectum from the other two species included in this study (H. exasperatum and H. horridum). Moreover, several genes encoding the major helodermatid toxins appeared to be extremely well-conserved under the influence of negative selection (but with these results regarded as preliminary due to the scarcity of available sequences). While the feeding ecologies of all species of helodermatid lizard are broadly similar, there are significant morphological differences between species, which impact upon relative niche occupation.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.