PRG-1 and 21U-RNAs Interact to Form the piRNA Complex Required for Fertility in C. elegans
Molecular CellPublished 20 June 2008Open access
Pedro J. Batista, J. Graham Ruby, Julie M. Claycomb, Rosaria Chiang, Noah Fahlgren, Kristin D. Kasschau
Citations640
SJR quartileQ1
SJR score9.05
SNIP2.89
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TL;DR
These findings demonstrate that 21U-RNAs are the piRNAs of C. elegans and link this class of small RNAs and their associated Piwi Argonaute to the maintenance of temperature-dependent fertility.
Abstract
In metazoans, Piwi-related Argonaute proteins have been linked to germline maintenance, and to a class of germline-enriched small RNAs termed piRNAs. Here we show that an abundant class of 21 nucleotide small RNAs (21U-RNAs) are expressed in the C. elegans germline, interact with the C. elegans Piwi family member PRG-1, and depend on PRG-1 activity for their accumulation. The PRG-1 protein is expressed throughout development and localizes to nuage-like structures called P granules. Although 21U-RNA loci share a conserved upstream sequence motif, the mature 21U-RNAs are not conserved and, with few exceptions, fail to exhibit complementarity or evidence for direct regulation of other expressed sequences. Our findings demonstrate that 21U-RNAs are the piRNAs of C. elegans and link this class of small RNAs and their associated Piwi Argonaute to the maintenance of temperature-dependent fertility.
Keywords
Agricultural and Biological SciencesBiochemistry, Genetics and Molecular Biology
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