本课题围绕本课题组通过miRNA芯片筛选出的在CFTR基因敲除小鼠睾丸组织显著高表达的miR-15b，研究其在精子发生中的作用机制。1）首先研究CFTR在生精细胞对miR-15b 的调节作用。验证CFTR的变异是否通过热休克蛋白Hsp90的介导与Ago2蛋白的浆/核定位有关，并探讨Ago2是否在miR-15b的启动子调节miR-15b的转录过程。2）应用细胞株模型明确miR-15b是否通过对Cdc25a的3-UTR区域的结合调节其表达；miR-15b过量的情况下是否会降低Cdc25a的表达，影响翻译;用在生精细胞高表达miR-15b的转基因小鼠模型观察在过表达miR-15b的情况下，是否会导致精子发生的功能受损并鉴定出调控的靶基因； 3）进一步观察miR-15家族成员在睾丸，精子和精浆，血浆的表达情况，明确其在几类病理情况的表达变化规律，并探讨其用于检测睾丸生精状况的可行性。

The purpose of the grant is to confirm the abnormal expression of miR-15b in CFTR knockout mice testis and elucidate the role of miR-15b in spermatogeneis and the related regulatory pathway during the pathophysiological process,including:1) Analysis and confirm the relevance between CFTR and miR-15b and elucidate the mechanistic link of CFTR and miR-15b during the spermatogenesis process.Whether the mutation of CFTR could affect Ago2 protein nuclear/cytoplasm shuttle through Hsp90 protein mediation and whether Ago2 could regulate miR-15b transcription through binding of its promoter.2) Using cell culture model to determine whether miR-15b regulate Cdc25a gene expression through targeting 3'-UTR region; and whether overexpression of miR-15b would reduce Cdc25a gene translation； further clarify whether transgenic overexpression of miR-15b could compromise spermatogenesis and what targets the miR-15b regulate. 3) Detect the expression of miR-15 famliy members in testis, sperm, seminal plasma and plasma to evaluate their expression changes in pathological conditions and further evaluate the possibility of using the expression levels of miR-15 as biomarker to detect spermatogenesis status in male infertility clinic.