Department of Biological Sciences, Graduate School of Science , The University of Tokyo , Tokyo 113-0032 , Japan.
Chem Rev. 2018 Apr 25;118(8):4404-4421. doi: 10.1021/acs.chemrev.7b00393. Epub 2017 Dec 27.
PIWI-interacting RNAs (piRNAs) are germline-enriched small RNAs that control transposons to maintain genome integrity. To achieve this, upon being processed from piRNA precursors, most of which are transcripts of intergenic piRNA clusters, piRNAs bind PIWI proteins, germline-specific Argonaute proteins, to form effector complexes. The mechanism of this piRNA-mediated transposon silencing pathway is fundamentally similar to that of siRNA/miRNA-dependent gene silencing in that a small RNA guides its partner Argonaute protein to target gene transcripts for repression via RNA-RNA base pairing. However, the uniqueness of this piRNA pathway has emerged through intensive genetic, biochemical, bioinformatic, and structural investigations. Here, we review the studies that elucidated the piRNA pathway, mainly in Drosophila, by describing both historical and recent progress. Studies in other species that have made important contributions to the field are also described.
PIWI 相互作用 RNA（piRNAs）是富含于生殖细胞的小 RNA，可调控转座子以维持基因组完整性。为实现这一功能，piRNAs 在从 piRNA 前体被加工后，大多数 piRNA 前体是基因间 piRNA 簇的转录本，与生殖细胞特异性 Argonaute 蛋白（PIWI 蛋白）结合，形成效应复合物。这种 piRNA 介导的转座子沉默途径的机制与 siRNA/miRNA 依赖性基因沉默的机制基本相似，即小 RNA 引导其伴侣 Argonaute 蛋白通过 RNA-RNA 碱基配对靶向基因转录本进行抑制。然而，通过深入的遗传、生化、生物信息学和结构研究，这种 piRNA 途径的独特性逐渐显现。在这里，我们通过描述历史和最新进展，综述了阐明果蝇中 piRNA 途径的研究。同时也描述了其他物种的研究对该领域的重要贡献。
