近来研究发现小RNA(small RNAs)可作为转录后及翻译水平上基因表达调节的重要调节因子, 利用小RNA来阐明调节精子发生的分子机制取得了显著进展。这些小RNA主要分为3类, 即小干扰RNA(siRNA)、微小RNA(miRNA)以及与piwi蛋白相互作用的RNA(piRNA)。在减数分裂和精子发生过程中, 小RNA具有多种生物学功能, 如利用siRNA体外转染或体内注射来敲低特定基因从而研究该基因在精子发生过程中的作用; miRNA可能参与精子发生中有丝、减数及后减数分裂阶段的基因表达调节; piRNA主要参与调节雄性生殖细胞减数及后减数分裂的过程, 在精子发生中起抑制反转录转座子(retrotransposons)的作用。文章对小RNAs合成、作用机制、功能及展望等最新进展进行了综述。
Small RNA molecules (small RNAs) have recently emerged as important regulators of gene expression at the post-transcriptional or translation level. Significant progress has recently been made in utilizing small RNAs to elucidate the molecular mechanisms regulating spermatogenesis. There are three major small RNAs: small interfering RNAs (siRNAs), microRNAs (miRNAs), and piwi-interacting RNAs (piRNAs). Small-RNAs have diverse biological functions in meiosis and spermatogenesis, In vitro or in vivo, use of siRNA to knockdown genes is a way to study the function of genes of intrest in spermatogenesis. miRNA can be involved in the regulation of mitosis, meiosis, and postmeiosis in spermatogenesis. piRNAs are mainly involved in regulating the process of meiosis and postmeiosis, and repressing retrotransposon transposition in male germline cells. In this paper, we reviewed recent works on the synthesis, mechanism, function, and outlook of smallRNAs.
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