哺乳动物精子发生中减数分裂的起始

生殖细胞的发生、增殖和分化是生命科学领域研究的重要课题之一. 生殖是所有动物赖以生存的基础，精子发生是完成繁殖所必须经历的过程，其最终目的是源源不断地产生单倍体精子.精子发生过程本身是一个复杂特殊的细胞增殖与分化过程,其中减数分裂是精子发生最重要的步骤,但关于减数分裂如何精确起始的分子机制仍知之甚少.已有报道发现,维甲酸（RA）调控Stra8可能是哺乳动物减数分裂起始的机制之一，Nanos2、Boule对RA-Stra8通路具有重要的调控作用. 本文对哺乳动物精子发生中减数分裂起始的相关研究进展进行综述.

The Meiosis Initiation of Mammalian Spermatogenesis

Reproduction is required for the survival of all animals. Germ cell development, proliferation and differentiation are always the most important in life sciences. Spermatogenesis is an essential and complex development process that ultimately results in production of haploid spermatozoa. Spermatogenesis is a special process of cell proliferation and differentiation which undergoes type A spermatogonia proliferation, type B spermatogonia differentiation into spermatocyte, round spermatid formation through meiosis and these cells will final develop into mature sperm. The initiation of germ cells meiosis is a critical step for spermatogenesis, however, the regulation of meiosis initiation at the molecular level still remains unclear. In recent studies, it has been widely accepted that Stra8 regulation by RA might be the main mechanism of meiosis initiation in mammalian spermatogenesis. Nanos2 and Boule could be involved in the regulation of RA-Stra8 signal pathway. In this paper, we reviewed the recent progress about meiosis initiation during mammalian spermatogenesis.