芳香化酶是控制动物体内雄激素转变为雌激素的关键酶，Foxl2促进芳香化酶cyp19a1基因表达，foxl2对卵巢发育有重要作用。近年研究发现，foxl2的旁系同源基因foxl3可能参与精巢发育。我们的前期研究表明，foxl3在石斑鱼由雌转雄的过程中表达量迅速升高；同时我们也验证了rec8，一种精子发育的关键基因在斜带石斑鱼精巢中高表达，双荧光素酶检测显示foxl3下调了rec8的表达。上述结果提示，foxl3和rce8在石斑鱼精巢发育中存在联系。因此，我们通过激素诱导方法，设计石斑鱼性腺发育由雌到雄再转到雌的连续变化过程，以脑-垂体-性腺轴调控为指导思想，研究foxl2/foxl3 - cyp19a1/ p450arom - 性类固醇激素轴在石斑鱼性别调控中的作用，并辅以foxl3表达增强和抑制实验，探讨foxl3与精子发育相关基因rec8的作用关系，为石斑鱼性别发育的调控提供理论依。

Aromatase is a key enzyme which makes androgen transformed into estrogen, Foxl2 promote the aromatase cyp19a1 gene expression. Foxl2 plays an important role in ovarian development and preserve ovarian function in many researches, but recent studies showed that, one of foxl2 prologs foxl2b, named foxl3 nowadays, plays new function in testis development. Our search testified the results that the expression levels of foxl3 unregulated during the sex reversal from female to male in orange spotted grouper. Rec8 is an essential key gene in spermatogenesis, which is crucial for the initiation of meiosis. We found that foxl3 could affect the expression of rec8 in grouper, and the foxl3 binding site was found on the promoter of rec8 gene, suggesting that the high expression of foxl3 in male gonads of grouper may be related to sperm development in the testis. .We designed a hormonal induced experiments in this project, make the grouper could undergo sex change from female to male, and the male to the female. We detect the genetic pathway of foxl3 in two directions mentioned above, with the method of increasing and inhibiting expression foxl3, combining immune coprecipitation of chromatin, loss of gel block experiment, the promoter mutant, dual luciferase report system and other technical methods, to explore the function of aromatase gene and Foxl2/foxl3 with grouper sex differentiation and transformation, objective to clarify the molecular mechanism of grouper gender differentiation and transformation.