Investigation of ER alpha expression on male behavior under field conditions

描述(由申请人提供)：群体中的个人经常表现出不同的社会性行为(例如，配对关系；父母照顾)，导致不同的生殖行为模式。在哺乳动物物种中调节社会性行为的新兴模式是复杂的，涉及到多种神经源性和环境因素。在过去的二十年里，实验室研究提供了大量关于特定神经生物学机制的信息，这些机制规范了与交配和生殖相关的社会行为。然而，仍然有必要在生态相关的背景下进行研究，以验证这些神经生物学调节机制在野外种群中具有生物学重要性。来自实验室的研究数据表明，雌激素通过雌激素受体α(ER？)作用，影响雄性哺乳动物社会性行为的许多方面，包括从属关系、攻击性、交配和父亲照顾，并表明ER？表情在自然界中对这些男性行为起到了中介作用。草原田鼠(Microtus Ochrogaster)是研究社会一夫一妻制行为的神经生物学机制的流行实验室模型。然而，在自然界中，雄性草原田鼠在社会和基因一夫一妻制方面表现出相当大的种群内和种群间的差异。增强的急诊室？在实验室条件下，雄性草原田鼠杏仁内侧核(Mea)的表达与亲社会行为的减少有关。我们提出的这项研究将利用草原田鼠种群之间自然发生的行为和神经解剖差异来测试ER？在0.1公顷半自然围栏中放生的个体中男性社会和基因一夫一妻制指数的表现。我们的研究将是第一次评估ER的作用？在基于种群和生态相关的框架内，对雄性草原田鼠的社会性行为的表达进行检验，以检验ER？表情是自然界中男性行为的重要生物学中介。此外，我们还计划使用RNAi来抑制男性ER？在MeA中的表达，以测试ER的直接因果效应？在MEA中对男性社会和生殖行为的表达，而不是像在实地研究中经常出现的那样，只是寻找相关性。我们预测高ER的男性？表情会有更大的家庭范围，表现出较少的家庭范围重叠和与单一女性的社会联系，不太可能是雌性鸟巢的居民，以及与雌性更多的父系后代比ER水平较低的雄性？表情。检查ER变异的后果？在一个几乎可以对行为产生生态和社会影响的完整剧目的环境中，表达将提供从实验室实验中无法获得的信息。这种方法是顺理成章的下一步探索ER是否存在个体差异？表达在自然界中影响男性的社会性行为，对于将使用动物模型的实验室发现的结果转化为治疗和理解人类社交缺陷障碍至关重要。

DESCRIPTION (provided by applicant): Individuals within a population often display variation in sociosexual behaviors (e.g., pair-bonding; parental care), resulting in different patterns of reproductive behavior. The emerging model for the regulation of sociosexual behavior in mammalian species is complex, involving multiple neurogenic and environmental factors. Laboratory studies during the past two decades have provided a wealth of information on specific neurobiological mechanisms that regulate social behaviors associated with mating and reproduction. However, there remains a crucial need for studies within ecologically relevant contexts to validate these neurobiological regulatory mechanisms as biologically important in field populations. Data from laboratory studies demonstrate that estrogen, acting via estrogen receptor alpha (ER?), influences many aspects of sociosexual behavior in male mammals including affiliation, aggression, mating, and paternal care and suggest that variation in ER? expression is contributing to the mediation of these male behaviors in nature. The prairie vole (Microtus ochrogaster) is a popular laboratory model for studying neurobiological mechanisms of behavior involved in social monogamy. Nonetheless, male prairie voles in nature show considerable within and between population variation in social and genetic monogamy. Enhanced ER? expression in the medial amygdala (MeA) is associated with decreased prosocial behavior in male prairie voles under laboratory conditions. The study we are proposing will utilize naturally occurring variation in behavior and neuroanatomy between populations of prairie voles to test the effect of ER? expression on indices of male social and genetic monogamy among individuals released into 0.1 ha semi- natural enclosures. Our study will be the first to assess the role of ER? expression on sociosexual behavior in male prairie voles within a population-based and ecologically relevant framework to test the hypothesis that ER? expression is a biologically important mediator of male behavior in nature. Furthermore, we also plan to use RNAi to inhibit male ER? expression in the MeA to test for a direct causative effect of ER? expression in the MeA on male social and reproductive behavior, rather than just searching for a correlation as is often the case in field studies. We predict that males with highe ER? expression will have larger home ranges, show less home range overlap and social association with a single female, be less likely to be a resident at a female's nest, and sire offspring with more females than males with lower levels of ER? expression. Examining the consequences of variation in ER? expression in a milieu in which almost the complete repertoire of ecological and social influences on behavior can occur will provide information that cannot be obtained from laboratory experiments. This approach is the logical next step to explore whether individual differences in ER? expression affect male sociosexual behavior in nature and is essential for translating the results from lab findings using animal models into treating and understanding human social deficit disorders.