The beneficial effects of cumulus cells and oocyte-cumulus cell gap junctions depends on oocyte maturation and fertilization methods in mice

PeerJ

article

Cheng-Jie Zhou¹  Sha-Na Wu¹  Jiang-Peng Shen¹  Dong-Hui Wang¹  Xiang-Wei Kong¹  Angeleem Lu¹  Yan-Jiao Li¹  Hong-Xia Zhou¹  Yue-Fang Zhao¹  Cheng-Guang Liang¹ 

[1] The Research Center for Laboratory Animal Science, College of Life Science, Inner Mongolia University

关键词: Oocyte;    Cumulus cells;    Gap junction;    Maturation;    Fertilization;    Early embryo development;   

DOI  :  10.7717/peerj.1761

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Cumulus cells are a group of closely associated granulosa cells that surround and nourish oocytes. Previous studies have shown that cumulus cells contribute to oocyte maturation and fertilization through gap junction communication. However, it is not known how this gap junction signaling affects in vivo versus in vitro maturation of oocytes, and their subsequent fertilization and embryonic development following insemination. Therefore, in our study, we performed mouse oocyte maturation and insemination using in vivo- or in vitro-matured oocyte-cumulus complexes (OCCs, which retain gap junctions between the cumulus cells and the oocytes), in vitro-matured, denuded oocytes co-cultured with cumulus cells (DCs, which lack gap junctions between the cumulus cells and the oocytes), and in vitro-matured, denuded oocytes without cumulus cells (DOs). Using these models, we were able to analyze the effects of gap junction signaling on oocyte maturation, fertilization, and early embryo development. We found that gap junctions were necessary for both in vivo and in vitro oocyte maturation. In addition, for oocytes matured in vivo, the presence of cumulus cells during insemination improved fertilization and blastocyst formation, and this improvement was strengthened by gap junctions. Moreover, for oocytes matured in vitro, the presence of cumulus cells during insemination improved fertilization, but not blastocyst formation, and this improvement was independent of gap junctions. Our results demonstrate, for the first time, that the beneficial effect of gap junction signaling from cumulus cells depends on oocyte maturation and fertilization methods.

【 授权许可】

CC BY