附睾头部上皮细胞Dicer1调控精子小RNA影响子代健康及其机制的研究

近年证据显示，附睾精子小RNA等表观信息能传给子代并影响其健康，但分子机制尚不清楚。我们前期工作表明，miRNA合成酶Dicer1在附睾头部高表达，将其敲除后附睾头部上皮细胞miRNA下降而小鼠繁殖能力并无变化。随后，我们又发现此敲除鼠附睾尾部精子miRNA、tsRNA均发生改变。更有趣的是，tsRNA比miRNA变化更大，而且其子代的代谢功能表现异常。提示Dicer1敲除引起附睾上皮细胞和精子小RNA变化并不改变生育能力，但可能在编码父本信息及其影响子代健康中扮演重要角色。所以，本项目拟利用附睾Dicer1敲除模型并结合受精卵小RNA微注射技术以及临床辅助生殖的数据和手段，围绕附睾上皮细胞和精子小RNA变化对子代健康影响及其机理进行深入研究。成果不仅对理解精子表观信息代间传递调控的分子机制具有重要意义，而且展示了附睾可调控子代健康的新功能、新亮点，引领附睾基础和应用研究走向新的方向。

Recent studies have indicated that epididymal sperm miRNA or tsRNA can be delivered to the zygote at fertilization and affect the health status of offspring. However, the mechanisms of sperm small RNA remodeling during post-testicular maturation in the epididymis and this reprograming in intergenerational epigenetic inheritance are unclear. Our previous works showed that Dicer1 was highly expressed in the caput of mouse epididymis and the deletion of Dicer1 gene resulted in the significant decrease of miRNA expression in the epithelial cells of epididymis, but the fertilizing ability of male dicer1-/- mice had no evident difference compared with their control. Subsequently, we further found that miRNA and tsRNA in the sperm of cauda epididymis of dicer1-/- mice display markedly alternation. More interestingly, tsRNA has a bigger change than miRNA and the offspring produced from dicer1-/- mice showed the metabolic disorder. This suggests that small RNAs transformation by the regulation of dicer1 in epididymis play an important role in the reprograming in intergenerational epigenetic inheritance. Therefore, the project will aim to investigate the role and molecular mechanism of dicer1-induced small RNA change in intergenerational epigenetic inheritance by the dicer1-/- mice model, small RNA microinjection manipulation, as well as clinical data and assisted reproductive technology. These works will be helpful to understand the mechanism by which sperm regulate the intergenerational epigenetic inheritance. Moreover, this achievement can show new features and highlights of the epididymal function in the regulation of offspring health. This research model will lead the basic and applied research of epididymis to a new direction.