DISSERTATION RESEARCH: The (epi)genetic basis of increased MUP expression during rapid adaptation to sociality in MUS

社会选择是进化的一种形式，是社会竞争的结果，作用于求偶、资源竞争、社会优势和群体行为所必需的特征。通过实验控制社会选择的人工选择实验是一种用于理解行为遗传基础的最新技术。虽然这些实验揭示了社会选择下的许多特征，但它们仅限于无脊椎动物群体。此外，现在的研究表明，生物体可以通过非基因组表观遗传对社会环境的变化做出反应，其中对环境的表型反应传递给后代。该项目通过研究实验室繁殖的野生小鼠重新引入高人口密度和社会选择机会的行为，遗传和表观遗传反应来解决我们理解中的这些差距。预测是，在实验室条件下繁殖的小鼠，在没有社会选择的情况下，下调或消除了只在强烈的社会选择中相关的代价高昂的特征。数据显示，将小鼠重新引入社会环境中会迅速增加雄性交配成功率，但会降低竞争环境中的生存率，增加雄性信号传导和吸引力，并增加雄性主要尿蛋白（MUP）的表达，MUP是小鼠通信中的主要信号。已知MUP受表观遗传的调节，但其功能仍不清楚。该项目现在研究增加MUP表达的行为意义以及因果遗传和表观遗传机制。它展示了哺乳动物如何对社会环境的变化做出反应，并将通过展示适应性和沟通在社会环境中的变化来促进我们对行为生态学的理解。它还将继续鼓励本科生和高中生参与科学发现，鼓励他们在研究中发挥独立作用，并在会议上介绍他们的工作。

Social selection is a form of evolution that results from social competition, and acts on traits necessary for courtship, competition for resources and social dominance, and group behaviors. Artificial selection experiments that experimentally control social selection are a recent technique used to understand the genetic basis of behavior. While these experiments have revealed many traits under social selection, they have been limited to invertebrate groups. Moreover, research now indicates that organisms can respond to changes in the social environment via non-genomic epigenetic inheritance, where phenotypic responses to the environmental are transmitted to subsequent generations. This project addresses these gaps in our understanding by examining the behavioral, genetic, and epigenetic responses of laboratory-bred wild mice reintroduced to high population density and the opportunity for social selection. The prediction is that mice bred under laboratory conditions, where social selection is absent, down-regulate or eliminate costly traits that are only relevant during intense social selection. Data show that reintroduction of mice to a social environment rapidly increases male mating success but decreases survivorship in competitive environments, increases male signaling and attractiveness, and increases male expression of Major Urinary Proteins (MUPs), a primary signal in mouse communication. MUPs are known to be regulated by epigenetic inheritance, but the function remains unknown. This project now investigates the behavioral significance of increased MUP expression and the causal genetic and epigenetic mechanisms. It demonstrates how mammals respond to changes in the social environment, and will contribute to our understanding of behavioral ecology by showing how fitness and communication vary across social environments. It also will continue to engage undergraduate and high school students in scientific discovery by encouraging them to take independent roles in the research and to present their work at conferences.