The RNase PARN-1 Trims piRNA 3' Ends to Promote Transcriptome Surveillance in C. elegans
UMass Chan AffiliationsProgram in Molecular Medicine
Program in Bioinformatics and Integrative Biology
RNA Therapeutics Institute
KeywordsBiochemistry, Biophysics, and Structural Biology
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AbstractPiwi-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.
SourceCell. 2016 Feb 25;164(5):974-84. doi: 10.1016/j.cell.2016.02.008. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/25942
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