The RNase PARN-1 Trims piRNA 3' Ends to Promote Transcriptome Surveillance in C. elegans

Cell. 2016 Feb 25;164(5):974-84. doi: 10.1016/j.cell.2016.02.008.

Abstract

Piwi-interacting RNAs (piRNAs) engage Piwi proteins to suppress transposons and are essential for fertility in diverse organisms. An interesting feature of piRNAs is that, while piRNA lengths are stereotypical within a species, they can differ widely between species. For example, piRNAs are mainly 29 and 30 nucleotides in humans, 24 to 30 nucleotides in D. melanogaster, and uniformly 21 nucleotides in C. elegans. However, how piRNA length is determined and whether length impacts function remains unknown. Here, we show that C. elegans deficient for PARN-1, a conserved RNase, accumulate untrimmed piRNAs with 3' extensions. Surprisingly, these longer piRNAs are stable and associate with the Piwi protein PRG-1 but fail to robustly recruit downstream silencing factors. Our findings identify PARN-1 as a key regulator of piRNA length in C. elegans and suggest that length is regulated to promote efficient transcriptome surveillance.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Argonaute Proteins / metabolism
  • Caenorhabditis elegans / metabolism*
  • Caenorhabditis elegans Proteins / metabolism
  • Exoribonucleases / chemistry
  • Exoribonucleases / metabolism*
  • Metabolic Networks and Pathways
  • Molecular Sequence Data
  • Mutation
  • RNA Processing, Post-Transcriptional*
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Sequence Alignment
  • Transcriptome

Substances

  • Argonaute Proteins
  • Caenorhabditis elegans Proteins
  • PRG-1 protein, C elegans
  • RNA, Small Interfering
  • Exoribonucleases
  • poly(A)-specific ribonuclease