Independent Evolutionary Origins of Tetrodotoxin Resistance as a Test of the Geographic Mosaic of Coevolution

河豚毒素抗性的独立进化起源作为共同进化地理镶嵌的检验

• 批准号: 0212065
• 负责人: Edmund Brodie, Jr
• 金额: $ 3.2万
• 依托单位: Utah State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-15 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0212065&HistoricalAwards=false
• 关键词: Independent; Evolutionary; Origins; Tetrodotoxin; Resistance

Evidence for arms-race coevolution between predator and prey will beevaluated in a unique natural interaction between toxic newts and theirresistant snake predators. Newts possess the neurotoxin tetrodotoxin(TTX), which blocks sodium channels in nerves and muscles. No knownpredator can ingest TTX and survive except for garter snakes of thegenus Thamnophis. Previous work demonstrated that predator and prey havematched levels of defensive and exploitative abilities, but the sourceof newt toxicity is still unknown. High Performance LiquidChromatography (HPLC) will be used to assay levels of toxin inlaboratory bred and reared newts to determine whether the requisiteindividual, genetic and population variation exists for newts to evolvein response to predators, allowing an evaluation of whether observedpatterns of matching are consistent with an arms race view ofcoevolution. Understanding the interactions between species that drivecoevolution is a major goal of evolutionary biology. Coevolution, inwhich one species evolves in response to another species, is thought tobe one of the major engines of biodiversity. Although coevolution isthought to be a common outcome of many ecological interaction, there arestrong theoretical and empirical reasons to suspect that predator-preyinteractions might be different. This research will shed important lighton natural variation in an important neurotoxin, TTX, which is usedwidely in studies of nerve function and development, by identifying thesources of TTX in amphibians.

捕食者和猎物之间的军备竞赛协同进化的证据将在有毒蝾螈和它们的抵抗性蛇类捕食者之间的独特自然相互作用中进行评估。蝾螈拥有神经毒素河豚毒素（TTX），它可以阻断神经和肌肉中的钠通道。没有已知的捕食者可以摄取TTX和生存，除了束带蛇属。先前的研究表明，捕食者和猎物的防御和利用能力已经达到了相当的水平，但蝾螈毒性的来源仍然是未知的。高效液相色谱法（HPLC）将被用来分析实验室繁殖和饲养的蝾螈中毒素的水平，以确定蝾螈是否存在必要的个体、遗传和种群变异，以进化出对捕食者的反应，从而评估配对的模式是否与共同进化的军备竞赛观点一致。理解物种之间的相互作用是进化生物学的一个主要目标。共同进化，即一个物种进化以回应另一个物种，被认为是生物多样性的主要引擎之一。虽然协同进化被认为是许多生态相互作用的共同结果，但有强有力的理论和经验理由怀疑捕食者-猎物相互作用可能有所不同。TTX是一种重要的神经毒素，广泛应用于神经功能和发育的研究。