Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia, QLD 4072, Australia; Institute of Biology Leiden (IBL), Leiden University, 2333 BE Leiden, the Netherlands.
Venom Evolution Lab, School of Biological Sciences, University of Queensland, St Lucia, QLD 4072, Australia.
Comp Biochem Physiol C Toxicol Pharmacol. 2021 Jul;245:109034. doi: 10.1016/j.cbpc.2021.109034. Epub 2021 Mar 22.
What factors influence the evolution of a heavily selected functional trait in a diverse clade? This study adopts rattlesnakes as a model group to investigate the evolutionary history of venom coagulotoxicity in the wider context of phylogenetics, natural history, and biology. Venom-induced clotting of human plasma and fibrinogen was determined and mapped onto the rattlesnake phylogenetic tree to reconstruct the evolution of coagulotoxicity across the group. Our results indicate that venom phenotype is often independent of phylogenetic relationships in rattlesnakes, suggesting the importance of diet and/or other environmental variables in driving venom evolution. Moreover, the striking inter- and intraspecific variability in venom activity on human blood highlights the considerable variability faced by physicians treating envenomation. This study is the most comprehensive effort to date to describe and characterize the evolutionary and biological aspects of coagulotoxins in rattlesnake venom. Further research at finer taxonomic levels is recommended to elucidate patterns of variation within species and lineages.
哪些因素会影响一个多样化分支中高度选择的功能性状的进化？本研究以响尾蛇为模型组，在系统发生学、自然历史和生物学的更广泛背景下，研究毒液凝血毒性的进化历史。测定了蛇毒对人血浆和纤维蛋白原的凝血作用，并将其映射到响尾蛇的系统发育树上，以重建凝血毒性在整个群体中的进化。我们的结果表明，在响尾蛇中，毒液表型通常与系统发育关系无关，这表明饮食和/或其他环境变量在驱动毒液进化方面的重要性。此外，在人类血液中对毒液活性的显著种间和种内变异性突出了治疗蛇咬伤的医生所面临的相当大的变异性。本研究是迄今为止对响尾蛇毒液中凝血毒素的进化和生物学方面进行描述和特征描述的最全面的努力。建议在更精细的分类学水平上进行进一步的研究，以阐明种内和谱系内变异的模式。
