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、攻击性和父母照顾，都有神经内分泌基础，这在脊椎动物中既有生物学基础，又有很好的保守性。因此，动物模型，特别是那些已经描述了确定的神经内分泌和遗传与社会行为的联系的动物模型，是研究影响人类社会行为的激素和基因的宝贵系统。理想情况下，这样的模型很容易在它们的自然栖息地进行研究，在社会行为上与人类相当相似，在基因上容易驯化，并且与之合作的成本不高。我们一直在研究社会行为的神经内分泌和遗传基础，这是一个非常有希望的模型，白喉麻雀(Zonotrichia Albiollis)。这种原产于北美的鸣禽引起了行为生物学家的极大兴趣，因为它的羽毛多态可以预测一个人的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表明，冠上有白色条纹(WS)的个体更具竞争力和攻击性，而拥有棕色条纹(TS)的鸟类更容易受到父母的照顾。颜色多态与2号染色体上的结构重排有关；所有WS个体都有重排的染色体(2M)的副本，而TS变型的人对于野生型染色体是纯合子的。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，从而有助于冒险、攻击性和育儿。这些基因包括性腺类固醇受体、类固醇生成酶和5-羟色胺受体亚型，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，我们建议通过以下方式来评估这些基因：(1)其表达反映行为多态；(2)可能对多态行为的发展具有组织效应；以及(3)已被染色体排列直接改变以改变基因表达或功能的方式。总体而言，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宝贵的机会，因为在自由生活和实验室种群中，白喉雀之间的行为差异已经得到了很好的证明，而且染色体倒置已经明确地与行为多态有关。由于调节社会行为的基因和途径在不同物种之间是保守的，这些研究的结果将适用于理解人类攻击性和父母行为的潜在机制。 公共卫生相关性：影响人类健康的社会行为，包括竞争攻击性和父母关怀，在一定程度上受到荷尔蒙和基因表达的影响。在这里，我们将在一个具有自然多态的动物模型中研究这些影响，该模型提供了一个独特的机会来表征潜在的攻击性和父母教养过程。

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.