Social and Gonadal Control of Neural Gene Expression

男性和女性大脑和行为的差异主要是由于基因表达的时间、水平和位置的差异。即使在性别由染色体决定，性腺在分化过程中发挥核心作用的物种中，基因表达的确切性质也受到从营养到社会互动等一系列环境影响的影响。虽然我们对性腺类固醇如何影响大脑和行为的性别分化有了扎实的了解，但社会互动影响这一过程的机制仍然知之甚少。该项目开发了一种综合方法来研究大脑中基因表达在性别分化过程中的变化，在一个模型系统中，有可能通过实验解剖调节行为的性腺和社会影响。一种被充分研究的珊瑚鱼，蓝头濑鱼，表现出社会控制的功能性性别变化。当当地的优势雄性被移除时，一个大的雌性变成了雄性，甚至性腺去角质的雌性也变成了雄性行为表型。挑战在于从大脑中找出那些与行为相关的神经基因，这些基因在不变性的雌性和在自然环境中被诱导变性的雌性之间有不同的表达。这个项目的重点是开发分子技术来成功地解决这个问题，首先确定一些相关的基因，然后可以针对这些基因来寻找行为改变过程中表达的变化。这一结果对于进一步发展这一系统作为理解两性二态行为的神经基础的良好遗传模型具有重要意义。这项工作的影响将从神经科学扩展到动物行为、心理学，以及在水产养殖和鱼类养殖中的潜在应用。此外，该项目继续为学生提供出色的实地和实验室培训，这是一个有趣的项目，将动物行为、内分泌学和分子生物学结合起来。

Differences between male and female brains and behavior result primarily from differences in the timing, level and location of gene expression. Even in species where sex is determined chromosomally and the gonads play central roles in the differentiation process, the exact nature of gene expression is influenced by a host of environmental influences ranging from nutrition to social interactions. Although we are building a solid understanding of how gonadal steroids influence the sexual differentiation of brain and behavior, the mechanisms by which social interactions affect this process remain poorly understood. This project develops an integrative approach to how gene expression in the brain changes during sexual differentiation, in a model system where it is possible to experimentally dissect gonadal and social influences that regulate behavior. A well-studied reef fish species, the bluehead wrasse, exhibits socially-controlled functional sex change. When local dominant males are removed, a large female changes into a male, and even gonadectomized females change to male behavioral phenotypes. The challenge is to identify those neural genes from the brain relevant to the behavior that are differentially expressed, between females that do not change sex and those that are induced to change sex in their natural environment. This project has a focus on developing the molecular technology to successfully approach that question, to first identify some of the relevant genes that then can be targeted to look for changes in expression during the behavioral change. Results will be important for further developing this system as a good genetic model to understand the neural basis of sexually dimorphic behavior. The impact of this work will extend beyond neuroscience to animal behavior, to psychology, and to potential use in aquaculture and fish breeding. In addition, the project continues excellent field and laboratory training for students in an interesting project integrating animal behavior, endocrinology and molecular biology.