Pnldc1 Total RNA-seq of P18 Testis

PIWI-interacting RNAs(piRNAs) are required for transposon repression, de novo DNA methylation, epigenetic and post-transcriptional regulation of gene expression in the germline. A mist of piRNA biogenesis is the identification of the 3'-5' exnuclease that trimms the 3' end of piRNA intermediates to form mature piRNAs in mammals. Here, we show that mice deficient for PNLDC1, an evolutionarily conserved 3'-5' exonuclease, accumulate 3' untrimmed piRNA intermediates of 30~40nt. These 3' extended piRNA intermediates associate with PIWI proteins, but are impaired for function. Male Pnldc1 knockout mice display LINE1 derepression and are sterile owing to chimeric spermatogenetic arrest at spermatocyte and spermatid stages. Our findings illustrate the conserved role of mouse Pnldc1 in 3' trimming during piRNA maturation. However, since Pnldc1 knockout in mice creates phenotypes distinct from its reported interactive partner, Tdrkh, the panorama of participants in mammalian piRNA 3' end maturation may be more complex than previously speculated.