A Unique Natural Model for Studying the Mechanisms Underlying Social Behavior

描述（由申请人提供）：影响人类健康的社会行为，包括冒险、攻击和亲代照顾，具有神经内分泌基础，在脊椎动物中具有生物学基础和良好的保守性。因此，动物模型，特别是那些明确描述了神经内分泌和遗传与社会行为联系的动物模型，是研究影响人类社会行为的激素和基因的有价值的系统。理想情况下，这样的模型可以很容易地在它们的自然栖息地中进行研究，它们的社会行为与人类相当相似，在基因上易于处理，而且成本低廉。我们一直在研究社会行为的神经内分泌和遗传基础，在一个非常有前途的模型，白喉雀（斑鸠）。这种原产于北美的鸣禽已经引起了行为生物学家的极大兴趣，因为羽毛的多态性可以预测个体社会行为的许多方面。在动物的自然栖息地进行的数十项行为研究已经确定，冠上有白色条纹（WS）的个体更具竞争力和攻击性，而有褐色条纹（TS）的鸟类则更多地参与父母的照顾。颜色多态性与2号染色体的结构重排有关；所有WS个体都有一个重排染色体的拷贝（2m），而TS形态的个体则是野生型染色体的纯合。我们目前正在绘制2m染色体的图谱，并已经确定了一组有希望的神经内分泌基因，这些基因位于重排中，因此可能有助于行为表型，从而影响冒险、攻击和养育子女。这些基因包括一种性腺类固醇受体、一种类固醇生成酶和一种血清素受体亚型，已经被怀疑在包括人类在内的脊椎动物的社会行为中发挥作用。在这里，我们建议通过鉴定那些(1)表达反映行为多态性的基因来评估这些基因；(2)可能对多态行为的发展产生组织效应；(3)被染色体排列直接改变，可能改变基因表达或功能的。总的来说，白喉麻雀为研究社会行为的生物学基础提供了一个独特而有价值的机会，因为在自由生活和实验室种群中已经有了很好的记录，并且染色体倒置已经明确地与行为多态性联系在一起。由于调节社会行为的基因和途径在物种间是保守的，这些研究的结果将适用于理解人类攻击性和亲代行为的潜在机制。

DESCRIPTION (provided by applicant): Social behaviors that impact human health, including risk-taking, aggression, and parental care, have a neuroendocrine basis that is both biologically based and well conserved across vertebrates. Animal models, particularly those in which definitive neuroendocrine and genetic links to social behavior have been described, are therefore valuable systems in which to study the hormones and genes that influence human social behavior. Ideally, such models would be easily studied in their natural habitats, reasonably similar to humans in their social behavior, genetically tractable, and inexpensive to work with. We have been studying the neuroendocrine and genetic bases of social behavior in an exceptionally promising model, the white-throated sparrow (Zonotrichia albicollis). This songbird, which is native to North America, has generated a great deal of interest among behavioral biologists because of a plumage polymorphism that predicts many aspects of an individual's social behavior. Dozens of behavioral studies conducted in the animals' natural habitat have established that individuals with a white-stripe (WS) on the crown are more competitive and aggressive, and birds with a tan stripe (TS) engage in more parental care. The color polymorphism is associated with a structural rearrangement on chromosome 2; all of the WS individuals have a copy of the rearranged chromosome (2m), whereas those of the TS morph are homozygous for the wild-type chromosome. We are currently mapping the 2m chromosome and have identified a set of promising neuroendocrine genes that are located within the rearrangement and may therefore contribute toward the behavioral phenotype and thus to risk-taking, aggression, and parenting. These genes, which include a gonadal steroid receptor, a steroidogenic enzyme, and a serotonin receptor subtype, are already suspected to play a role in social behavior in vertebrates, including humans. Here, we propose to evaluate these genes by identifying those (1) whose expression mirrors the behavioral polymorphism; (2) that may have organizational effects on the development of polymorphic behavior; and (3) that have been directly altered by the chromosomal arrangement in ways that may alter gene expression or function. Overall, the white-throated sparrow represents a unique and valuable opportunity for studies of the biological bases of social behavior because the behavioral differences between the morphs are already well-documented in free-living and laboratory populations, and the chromosomal inversion has been definitively linked to the behavioral polymorphism. Because the genes and pathways that regulate social behavior are conserved across species, the results of these studies will be applicable to understanding the mechanisms underlying aggressive and parental behavior in humans. PUBLIC HEALTH RELEVANCE: Social behaviors that impact human health, including competitive aggression and parental care, are in part influenced by hormones and gene expression. Here, we will study these influences in an animal model with a natural polymorphism that provides a unique opportunity to characterize the processes underlying aggression and parenting.