雄激素调控泛素结合酶UBE2B表达的分子机理及其生物学意义

睾丸支持细胞(Sertoli cell)的雄激素受体（AR）在精子发生过程中具有非常重要的作用，其分子机理尚未明了。有研究表明，泛素结合酶Ube2b基因敲除小鼠表现为精子发生障碍和雄性不育；本实验室的研究表明，雄激素显著提高小鼠睾丸支持细胞UBE2B的表达水平。因此，我们推测Ube2b可能作为雄激素受体的靶基因之一，介导雄激素在精子发生过程中的作用。本项目将(1)采用基因过表达、RNA干扰和免疫印迹等方法，检测UBE2B对睾丸支持细胞中组蛋白H2A和H2B泛素化、H2AT120磷酸化和H3K4甲基化水平的影响；(2) 采用基因芯片技术，确定"AR-UBE2B通路"调控的基因谱；（3）采用免疫组织化学和PCR测序技术，确定UBE2B与男性不育症的相关性。该项目的实施，对于进一步阐明雄激素及其受体调节精子发生的分子机理具有重要的学术意义，也将为男性不育症的诊断与治疗提供新的思路。

The androgen receptor in Sertoli cell of the testis plays an important role in spermatogenesis, but the mechanism is not clear. It has been reported that knockout of ubiquitin-conjugating enzyme E2B (Ube2b) resulted in the disorders of spermatogenesis and male infertility in mice. Our previous data showed that androgen and its receptor significantly up-regulated the expression of Ube2b by directly binding to androgen receptor response element. Those data suggested that UBE2B worked as a message of androgen receptor to participate in spermatogenesis. The present studies plan (1) to detect the effects of UBE2B on ubiquitylation of H2A and H2B, H2AT120 phosphorylation and H3K4 methylation by gene over-expression, RNAi and western blotting; (2) to identify the genes regulated by "AR-UBE2B pathway" with mRNA microarray and RT-PCR; (3) to explore the relationship between the mutation, SNP and expression of UBE2B and male infertility by PCR sequencing and immunohistochemistry. The project is valuable to further clarify the molecular mechanisms of androgen and its receptor in spermatogenesis, which may supply a new clue for the diagnosis and treatment of male infertility.