鲤科鱼类的类固醇激素调控性别分化、性腺发育和生长代谢的机制研究及其水产应用

与哺乳动物不同，鱼类的性别分化和性腺发育的机制复杂且多样。虽然在哺乳动物和鱼类中均已发现类固醇激素对性别分化和性腺发育极为重要，但我们发现其执行功能、调控机制和互作通路等过程在两个物种中存在较大差异。我们在斑马鱼中对类固醇激素的合成进行了阻断（cyp17a1纯合子斑马鱼），构建了雄激素和雌激素缺乏的模型，发现鱼类中存在垂体的Fshβ在精巢发育/精子发生中的补偿机制和卵巢发育的可塑机制。因此，本项目首先拟围绕雄激素和雌激素维持精巢发育/精子发生和卵巢命运的机制进行研究。类固醇激素除了与性别分化和性腺发育紧密相关外，可能与生长和营养物质代谢紧密相关。所以，类固醇激素对鲤科鱼类（斑马鱼和鲤鱼）生长代谢的调控也是本项目将重点关注的。在完成上述基础研究的同时，我们拟将阻断类固醇激素合成的策略在鲤鱼中进行水产应用，努力获得“全雌”的鲤鱼品种，实现与生产的结合（2龄雌性鲤鱼的平均体重比雄性约高30%）。

Unlike mammals, sex differentiation and gonadal development in teleost fish show greater complexity and plasticity. Though sex steroids have been identified as key factors in maintaining sex differentiation and gonadal development, the precise function, regulation, and related signal pathway of sex steroids have highly diverged between the two species. Previously, we have blocked the synthesis of sex steroids by the knockout of cyp17a1 and established a model with androgen- and estrogen-deficiency in zebrafish. We observed the compensatory role of Fshβ signaling in maintaining testis development and spermatogenesis, as well as the plastic role of estrogens in maintaining ovary differentiation. Besides, we observed that sex steroids are closely related to nutrient metabolism, which may be the cause of sex dimorphism in growth. Therefore, in the present project, we firstly focus on the regulation of androgens and estrogens in maintaining testis.and ovary development, respectively. We would also elucidate the relationship between sex steroids and growth-metabolism. By establishing the sex steroids-deficient Cyprinus Carpio, we set out to obtain the all-female offspring to apply our investigations to the aquaculture.