Med13在卵母细胞减数分裂成熟、早期胚胎和生殖道发育中的功能研究

Mediator复合体是Pol II介导转录中的共激活因子，其亚基Med13在卵母细胞和二细胞前胚胎中高表达，Med13敲低处理会导致卵母细胞不成熟和早期胚胎发育停滞，其半基因敲除鼠表现阴道发育不全，该表型与人类生殖疾病MRKH综合征极为相似，但Med13是如何调控这些生理过程还不清楚。前期研究表明Med13参与调控卵母细胞染色体分离和胚胎基因组激活，并影响与生殖道发育相关基因表达。本项目以RNA干扰和基因敲除为手段，深入研究1）Med13敲低/除对卵母细胞成熟中染色体分离的影响，尤其对黏连蛋白形成与水解的影响；2）Med13敲低/除的发育停滞胚胎中转录被影响的基因类别、信号通路归属及相结合转录因子的种类，并通过外源表达相关通路中重要基因来挽救胚胎发育；3）Med13半敲除母鼠的生殖道上异常表达的基因并结合激素水平来寻找调控生殖道发育的重要机制，并探索Med13与人类MRKH综合征的关系。

Mediator Complex is an important co-activator involved in RNA polymerase II mediated transcription. Med13, a subunit of Mediator Complex, was highly expressed in oocytes and one/two-cell stage embryos. Med13 knockdown affected oocyte maturation and early embryo development. Full Med13 homozygous knockout mice died early while heterozygous knockout mice showed vaginal agenesis and this phenotype was very similar to MRKH disease in human. However, how does Med13 regulate these physiological processes is unclear. Our preliminary work shows that Med13 is involved in chromosome segregation and embryonic genome activation, and also regulates the expression of genes related to the reproductive tract development. Therefore, we will use gene RNAi in vitro and gene knockout in vivo technology in this project, to study 1) the effects of Med13 knockdown /knockout on chromosome segregation, especially on the formation and hydrolysis of Cohesin during oocyte maturation; 2) the categories, signal pathway and the kinds of same transcription factor combined of genes affected on transcription in the arrested Med13 knockdown/knockout embryos and try to overexpress some important genes in signal pathway to rescue the development of arrested embryos; 3) the abnormal genes expression on the reproductive tract of Med13 heterozygous knockout mice and try to find the mechanisms regulated the development of the reproductive tract in combination to endocrine secretion in vivo and the relationship between Med13 and human MRKH syndrome.