基因突变影响斑马鱼性征与繁殖行为的调控机制研究

Sex characters and mating behavior are inseparable. In zebrafish,there is no reports about the regulatary mechanism about sexual characteritics changes together with mating behavior caused by gene mutation. Based on the study of tdrd12 and cyp17a1 mutants whose phenotypes were absolutely different in primary sexual characteristics, secondary sexual characteristics, mating behavior been observed and androgen levels been detected,we conclude that the mating behavior and the maintenance of secondary sexual characteristics of zebrafish do not depend on the presence of germ cells in the gonadal tissue, but mainly on the androgen levels in their blood. Based on the previous results we have observed, utilizing behavioral analysis system, in situ hybridization, RNA-seq and other methods, tdrd12 and cyp17a1 mutant models were used for analyzing the differences of mating behavior, especially for the competitive courtship behavior among tdrd12 -/-, cyp17a1-/- and double homozygous mutants; elucidating the relationships among primary sex characteristics , secondary sex characteristics and the mating behavior as well as their regulatary mechanims; the analysis of genes and pathways associated with sex characteristics and mating behavior though RNA-seq data of hypothalamic-pituitary-gonadal axis.

性征与繁殖行为密不可分。在斑马鱼中，由基因突变引起的性征变化和繁殖行为差异的调控机制还未见报道。我们通过观察tdrd12和cyp17a1突变体第一性征、第二性征、繁殖行为的差异，以及血液中雄激素水平的检测，得出斑马鱼的繁殖行为以及第二性征的维持不依赖于性腺组织中生殖细胞的存在，但是依赖于血液中雄激素的水平。本项目旨在前期工作基础上，利用tdrd12，cyp17a1突变体模型，采用行为分析仪，原位杂交，RNA-seq等方法，追踪分析tdrd12-/-突变体，cyp17a1-/-突变体tdrd12-/-与cyp17a-/-双纯合突变体繁殖行为的差异，特别是不同突变体之间存在的竞争性求偶行为；阐明第一性征，第二性征以及繁殖行为之间的联系与调控机制；通过下丘脑-垂体-性腺调控轴转录组数据分析调控性征与繁殖行为的相关基因和通路。

性征与繁殖行为密不可分。Tdrd12和Cyp17a1突变体全雄化且不育，但它们的性征（第一性征和第二性征）和繁殖行为方式截然不同。本研究中，利用行为分析、RNA-seq等方法，系统性的阐明了第一性征，第二性征以及繁殖行为之间的联系与调控机制。结果表明：斑马鱼第二性的发生和斑马鱼雄性个体正确的交配行为完全不依赖于生殖细胞的存在，但依赖于性腺体细胞组织的调控。11-酮基睾酮（或睾酮）对雄性第二性征的发生以及正确的交配行为起着重要的作用。转录组数据和qRT-PCR结果显示dio2等基因可能是脑神经支配雄性交配行为的关键调控基因。本研究从分子内分泌水平深入分析了雄性性征（第一性征和第二性征）和繁殖行为差异的机制。