lncSR1在STRBP调控精子变形中的作用与机制研究

Spermiogenesis is the key step of spermatogenesis. However, mechanisms underlying the spermiogenesis have not been fully elucidated. STRBP, spermatid perinuclear RNA binding protein, is essential for spermiogenesis. Recently, applicant has obtained one lncRNA genes, lncSR1, which are specific-expressed in testes. Further study showed that lncSR1 could interact with STRBP and have a function that affected cell growth and reduce sperm amount. We also have obtained lncSR1 knockout mice. In addition, we found that multiple mRNAs could interact with STRBP and be regulate by STRBP. We proposed that the key STRBP-interacted lncRNA play an important role in spermiogenesis. Based on the super-resolution microscopy and KO mice models, RNA interference and other techniques, the project intends to identify the interaction domain between lncSR1 and STRBP protein respectively, investigate dynamic expression characteristics of lncSR1 and the effect of lncSR1 on spermiogenesis and elucidate the spermiogenesis mechanism regulated by lncSR1 and STRBP/lncSR1 complex via regulating those genes expressions of mRNA stability and spermiogenesis-related genes expression. The project will be the first to identify the key lncRNA affected spermiogenesis, reveal the mechanism that STRBP/lncRNAs complex regulated spermiogenesis, and provide a new perspective for the study of spermatogenesis and male sterility.

精子变形是精子发生的关键环节，然而调控精子变形的机制远未阐明。精子细胞核周围RNA结合蛋白STRBP对精子变形至关重要。申请人最近获得了一个睾丸特异性的长链非编码RNA lncSR1，发现其与STRBP存在相互作用，且具有影响细胞生长、减少精子数量的功能，并获得了其小鼠敲除模型。同时也发现多种精子发生相关基因mRNA与STRBP互作，且受其调控。我们推测STRBP互作关键lncRNA在精子变形中也扮演着重要角色。本项目拟利用超分辨显微成像技术并结合基因敲除模型：鉴定lncSR1与STRBP蛋白的互作结构域；探究lncSR1的动态表达特征及对精子变形的影响；阐明该lncRNA及互作复合体通过调控mRNA稳定性及精子变形相关基因表达影响精子变形的精细机制。本项目将率先发现调控精子变形的关键lncRNA，揭示STRBP及互作lncRNA影响精子变形的机制，为精子发生及雄性不育研究提供全新视角。

精子变形的调控机制远未阐明。关键睾丸特异性lncRNA对精子发生至关重要，缺失可导致不育，然而lncRNA在哺乳动物精子变形中的作用及机制尚不清楚。调控精子变形的关键蛋白STRBP与包括lncSR1在内的多种lncRNA互作，提示lncSR1可能对于精子变形具有重要作用。本项目以STRBP互作的lncSR1为切入点，研究lncRNA在精子变形中的作用。主要研究内容为：鉴定lncSR1与STRBP蛋白的互作结构域；研究lncSR1的动态表达特征及对精子变形的影响；阐明lncSR1及互作复合体调控精子变形的机制；拓展研究保守性睾丸特异性lncRNA对精子变形及雄性生育的影响。我们发现：1）STRBP与多种lncRNA及蛋白存在互作，可能通过调控细胞粘附、蛋白修饰及RNA代谢等过程影响精子变形；2）lncSR1敲除小鼠没有明显的生殖异常表型，lnSR1缺失导致STRBP表达上调，Cis调控潜在靶基因Cap5表达下调；3）Cpa5缺失对精子发生及小鼠生育也没有显著影响；4）lncSR1缺失小鼠对雷公藤甲素诱导的生殖毒性具有保护作用；5）保守的睾丸特异lnc2/4调控精子变形、小鼠渐进性不育；6）lncRNA AntiCabs1敲除未见生殖异常，反义编码基因Cabs1通过影响精子鞭毛形态导致雄性生育受损。本研究系统探讨了lncRNA在雄性生育中的作用，挖掘到了对精子变形具有重要调控作用的lncRNA，部分lncRNA的敲除未表现出生殖异常，提示lncRNA是功能冗余的，发挥作用可能是对基因表达或生物大分子的活性起到微调作用，lncRNA可能参与了不利胁迫诱导的生殖过程调控。本项目对于理解lncRNA在雄性生育中的作用及揭示相关男性不育疾病的病理机制具有重要意义。本项目资助下，共发表论文11篇，其中SCI论文10篇，申请发明专利5项。协助培养博、硕士研究生各3名。项目达到了预期目标。