Abstract:

microRNAs（miRNAs）， a class of newly found noncoding RNAs， which regulate gene expression at transcriptional level or post-transcriptional level， play fundamental roles in multiple biological processes， including cell differentiation， development and metabolism as well as disease processes. In the field of reproductive medicine， miRNAs have been proved to participate in the meiosis processes and development of spermatocyte and oocyte. It can regulate the early development of the mouse preimplantation embryos， and affect the expression of genes related to implantation. miRNAs also play a a critical role in the maintenance of stem cell self-renewal and pluripotency. An association may exist between human infertility with aberrant miRNA profiles of germ cell. In this review， mechanism and function of miRNAs， principal methodologies in the research of miRNAs and the latest development of miRNAs in reproductive development are stated.

Key words: miRNA, Germ cell, Embryonic stem cell