附睾区域特异增强子的鉴定和分析

Epididymis is a tubular organ exhibiting vectorial functions of sperm maturation and storage and also the idea organ for male contraception. A large number of epididymis-expressed genes have been characterized by a distinct temporal and spatial expression pattern within the organ. So far the molecular mechanism underlying the complex and delicate regulation of region-specific gene expression in epididymis is poorly understood. Among various cis-regulatory elements, enhancers are marked with highly cell-type-specific histone modification patterns, strongly correlate to cell-type-specific gene expression programs on a global scale, and are functionally active in a cell type-specific manner.In this study, we will systematically study region-specific enhancers in mouse epididymis using ChIP-seq and identify and analyze the active enhancers with the P300+H3K27ac+ in mouse caput and cauda epididymis. By this study, we will determine the genomic distribution of enhancers in mouse epididymis and enhancers-enriched DNA motifs and their associated transcription factors. We will also identify the important AR-binding sites located in active enhancer region and hopefully find new epididymis-specific promoters. Finally this study will provide important basis for further study of molecular mechanism of region-specific expression regulation in epididymis and clue for further research and development of novel male contraceptive drug.

附睾是精子成熟和储存的场所，也是男性避孕的理想靶器官。附睾基因表达存在着复杂精细的调控， 不同附睾区域基因表达各不相同，提供了一个不断变化的微环境, 精子在这样的环境中逐步获得了运动和受精能力.目前附睾区域特异基因表达调控机制基本上未知。在各类顺式调控元件中，增强子是不同细胞间变化最大的一类调控元件，在决定细胞特异表达方面最为关键。本项目准备利用ChIP-seq手段对小鼠附睾区域特异增强子进行系统性研究，用p300 和H3K27ac 染色质免疫共沉淀方法寻找并分析附睾附睾头部和尾部含有P300+H3K27AC+标记的活跃增强子。 通过本研究我们将初步阐明附睾头部和尾部的增强子在基因组分布和序列特征以及重要的结合蛋白，确认在附睾头部基因组可能发挥关键作用的AR结合位点并有望找到新的附睾特异调控序列，为进一步研究附睾基因区域特异表达调控机制奠定基础， 也为新型男性避孕药研发提供新的思路。

附睾是精子成熟和储存的场所，也是男性避孕的理想靶器官。附睾基因表达存在着复杂精细的调控， 不同附睾区域基因表达各不相同，提供了一个不断变化的微环境, 精子在这样的环境中逐步获得了运动和受精能力.目前附睾区域特异基因表达调控机制基本上未知。在各类顺式调控元件中，增强子是不同细胞间变化最大的一类调控元件，在决定细胞特异表达方面最为关键， 另外雄激素受体信号通路对附睾基因表达调控起主要作用，雌激素信号通路也参与附睾基因表达调控以及维持睾丸输出小管的正常功能起着重要作用。在本项目支持下，我们对附睾不同区域的LncRNA包括enhancer RNA的表达特性以及和附睾头部基因组中雄激素受体结合位点进行关联分析， 发现许多附睾特异的LncRNA可以关联一些附睾特异基因。 另外，我们还研究了雌激素受体在小鼠睾丸输出小管的基因组结合位点，发现许多离子通道和水通道是雌激素受体的直接靶基因。 在本项目资助下两篇研究论文发表，另外一篇已经成文并投稿。 本研究结果将为进一步研究附睾基因区域特异表达调控机制奠定基础， 也为新型男性避孕药研发和环境雌激素对男性生殖影响的分子机制提供新的思路。