Social Regulation of Brain and Behavior

两性之间的巨大差异通常在发育早期就已经确立，并在一生中保持不变。然而，在许多鱼类中，生殖功能表现出终生可塑性，性转变发生在不同的社会和生活史条件下。通过操纵蓝带虎鱼(Lythinknus Dalli)的社会群体组成，可以预测地诱导目标雌性的优势地位的建立和随后的性别变化。这只雌性在变身为雄性的过程中，表现出一系列刻板的行为、生理和解剖变化。人们可以使用支配地位的早期行为指标来检验推动社会地位提高和启动性别变化的机制。性激素参与了这两个过程的调节，但性腺产生的性类固醇在性别变化的早期阶段不会改变。然而，脊椎动物的大脑合成性类固醇，这些酶过程可以在几分钟内下调。目前的项目对社会地位的改变、神经类固醇途径的快速调节和性别变化的启动之间的关系进行了批判性的研究。通过测定大脑类固醇水平、将一种类固醇酶转化为另一种类固醇的速率以及观察动物的行为，人们可以确定社会和内分泌信号在调节成人性别变化方面的动态相互作用。性别差异的进化和发展对生物学家来说是一个至关重要的领域，这项工作的结果将加深我们对社会过程如何调节生殖行为、解剖学和生理学的理解。行为神经科学中心教育理事会的资源将用于招募妇女和少数群体参加通过这笔赠款提供的本科生和研究生培训机会，该中心在指导妇女和少数群体进行科学研究方面有着出色的记录。

Dramatic differences between the sexes are normally established early in development and remain fixed for life. However, in many fishes, reproductive function shows life-long plasticity, with sexual transitions occurring in response to varying social and life history conditions. By manipulating social group composition in bluebanded gobies (Lythrypnus dalli), one can predictably induce the establishment of dominance and subsequent sex change in a targeted female. This female exhibits a stereotyped sequence of behavioral, physiological and anatomical changes as she transforms into a male. One can use early behavioral indicators of dominance to examine the mechanisms that drive both increased social status and the initiation of sex change. Sex steroids have been implicated in the regulation of both of these processes, but gonadal production of sex steroids does not change in the early stages of sex change. However the vertebrate brain synthesizes sex steroids and these enzymatic processes can be down-regulated in minutes. The current project critically examines the relationship between changing social status, rapid regulation of neurosteroid pathways, and the initiation of sex change. Through the determination of brain steroid levels, the rates of enzymatic conversion of one steroid to another and observations of how the animals are behaving, one can determine the dynamic interactions between social and endocrine signals in regulating adult sex change. The evolution and development of sex differences is an area of fundamental importance for biologists and the results of this work will enhance our understanding of how social processes regulate reproductive behavior, anatomy and physiology. The resources of the Education directorate at the Center for Behavioral Neuroscience will be used to recruit women and minorities into the undergraduate and graduate training opportunities available through this grant and the PI has an outstanding record of mentoring women and minorities in scientific research.