The Genetics of Behavioral Reproductive Isolation in Threespine Sticklebacks

描述（由申请人提供）：尽管遗传对人类行为以及人类行为障碍的正常变异范围有重要贡献，但人们对影响任何生物体行为的基因知之甚少。特别是，目前很少有模型脊椎动物系统可以对自然远交种群的行为变异进行基因剖析。最近开发的三刺棘鱼（Gasterosteus aculeatus）遗传和基因组工具为在明确的生态和进化背景下研究行为变异的遗传基础提供了机会。三刺鱼的交配行为可能是所有动物系统中研究得最好的。先前的研究表明，雄性和雌性交配行为的差异导致刺鱼种群之间的生殖隔离，这些刺鱼种群已经适应了生活在一个湖泊的两种不同栖息地（“底栖”和“湖沼”）中。不列颠哥伦比亚省有多个湖泊，这些底栖和湖沼“物种对”已经在其中进化，并且每个湖泊的交配行为都独立发生了类似的变化。本研究的目的是利用数量性状基因座 (QTL) 作图来研究两个湖泊（Priest 和 Paxton）的底栖和湖沼刺鱼之间生殖隔离行为的遗传基础。这些实验种群将在完全自然的条件下在室外池塘中饲养并进行行为评估。通过研究与生殖隔离相关的行为表型（例如雄性筑巢行为和雌性交配偏好）的遗传基础，这项工作将测试孤立湖泊中平行物种对的刺鱼是否具有与生殖隔离相关的趋同行为的相似遗传结构。该项目还将测试影响生殖隔离行为的 QTL 是否不成比例地映射到影响已知对配偶选择重要的性状（例如体型和体型）的基因组区域。重要的是，这里提出的 QTL 作图实验将作为识别自然棘鱼种群行为差异背后的基因的第一步。刺鱼的结果可能对理解人类行为变异和行为障碍的遗传基础具有重要意义，因为行为背后的许多遗传和神经通路可能在鱼类和人类之间是保守的。此外，人类和刺鱼在相似的进化时间范围内迁移并适应了新的环境，这表明研究刺鱼行为变异的遗传结构与人类的类似研究有直接关系。

DESCRIPTION (provided by applicant): Although there is an important genetic contribution to the normal range of variation seen in human behaviors as well as human behavioral disorders, very little is known about the genes that influence behavior in any organism. In particular, there are currently few model vertebrate systems in which the study of behavioral variation in a natural, outbred population can be genetically dissected. The recent development of genetic and genomic tools for the threespine stickleback (Gasterosteus aculeatus) presents an opportunity to study the genetic basis of behavioral variation in a well-defined ecological and evolutionary context. The mating behaviors of the threespine stickleback are perhaps the best-studied of any animal system. Previous work has shown that divergence in male and female mating behaviors leads to reproductive isolation between stickleback populations that have adapted to living in two different habitats ('benthic' and 'limnetic') in a single lake. There are multiple lakes in British Columbia in which these benthic and limnetic 'species pairs' have evolved, and similar changes in mating behavior have occurred independently in each lake. The aim of this study is to investigate the genetic underpinnings of behaviors involved in reproductive isolation between benthic and limnetic sticklebacks from two lakes (Priest and Paxton) using quantitative trait locus (QTL) mapping. These experimental populations will be raised and behaviorally evaluated under fully natural conditions in outdoor ponds. By investigating the genetic basis of behavioral phenotypes involved in reproductive isolation (e.g., male nesting behavior and female mate preferences), this work will test whether parallel species pairs of sticklebacks in isolated lakes share similar genetic architectures for convergent behaviors involved in reproductive isolation. This project will also test whether QTL influencing behaviors involved in reproductive isolation map disproportionately to genomic regions affecting traits known to be important for mate selection, such as body size and shape. Importantly, the QTL mapping experiments proposed here will serve as a first step in the identification of genes that underlie behavioral differences in natural stickleback populations. Results in sticklebacks are likely to have important implications for understanding the genetic basis of behavioral variation and behavioral disorders in humans because many of the genetic and neural pathways that underlie behaviors are likely to be conserved between fish and humans. In addition, humans and sticklebacks have migrated and adapted to new environments over a similar evolutionary timeframe, suggesting that studying the genetic architecture of behavioral variation in sticklebacks has direct relevance to similar studies in humans.