Knockout Gene-Based Evidence for PIWI-Interacting RNA Pathway in Mammals

• Main Authors: Yinuo Li, Yue Zhang, Mingxi Liu
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2021-07-01
• Series: Frontiers in Cell and Developmental Biology
• Subjects: piRNA; meiosis; male infertility; RBPs; RNA binding proteins
• Online Access: https://www.frontiersin.org/articles/10.3389/fcell.2021.681188/full

The PIWI-interacting RNA (piRNA) pathway mainly consists of evolutionarily conserved protein factors. Intriguingly, many mutations of piRNA pathway factors lead to meiotic arrest during spermatogenesis. The majority of piRNA factor-knockout animals show arrested meiosis in spermatogenesis, and only a few show post-meiosis male germ cell arrest. It is still unclear whether the majority of piRNA factors expressed in spermatids are involved in long interspersed nuclear element-1 repression after meiosis, but future conditional knockout research is expected to resolve this. In addition, recent hamster knockout studies showed that a piRNA factor is necessary for oocytes—in complete contrast to the findings in mice. This species discrepancy allows researchers to reexamine the function of piRNA in female germ cells. This mini-review focuses on the current knowledge of protein factors derived from mammalian knockout studies and summarizes their roles in the biogenesis and function of piRNAs.