睾丸支持细胞蛋白质异戊二烯化通过影响血睾屏障的结构与功能调节精子发生的机制研究

支持细胞对精子发生至关重要。除了营养支持和内分泌调节，支持细胞还形成生精小管免疫特权重要保证的物理结构：血睾屏障。我们在上一个国家基金的工作中发现，抑制支持细胞的蛋白质异戊二烯化破坏了青春期小鼠睾丸的免疫特权而导致雄性不育，同时也引起血睾屏障的破坏，生精小管出现非梗阻性无精症类似的表型。进一步发现，成年后小鼠基底腔的精原干细胞数量逐步恢复，但是精子发生仍被阻滞在初级/次级精母细胞阶段，提示蛋白质异戊二烯化可能通过血睾屏障影响精子发生。本项目将利用支持细胞特异敲除蛋白质异戊二烯化的调节基因Ggpps的小鼠模型，比较成年和幼年小鼠睾丸支持细胞间血睾屏障和支持细胞与不同发育阶段生殖细胞间细胞连接的结构与功能改变，并从蛋白质异戊二烯化修饰通过Ras/MAPK影响细胞连接蛋白表达，以及通过Rab影响细胞连接蛋白膜泡运输上膜的角度研究其中的分子机制，同时探讨以血睾屏障障碍为靶点治疗NOA 的可能性。

The function of Sertoli cell is very important for mammalian spermatogenesis. Besides the nutrition support and endocrine regulation, Sertoli cells build a critical physical structure for the maintenance of immune privilege inside seminiferous tubules: blood-testes barrier (BTB). We found that the inhibition of protein prenylation in Sertoli cells disturbed the immune privilege in pubertal mice and resulted in adulthood infertility because of the loss of spermatogonia. And the BTB was also damaged and the morphology of testes is Sertoli cell only syndrome like NOA patients. Although the spermatogonia in the basement compartment recovered gradually in adult testis, the spermatogenesis is still blocked at spermatocyte stage. In this project, we will further examine the difference of the structure and function of BTB and cell junction between Sertoli cells and Sertoli cell and developing spermatocytes in adult and pubertal mice. The gene expression and membrane translocation of cell junction proteins dependent on prenylation regulated Ras/MAPK and Rab activity was also studied to explore the underline molecular mechanism. We will also try to find the possibility that BTB as a therapeutic target for NOA treatment.