Abstract
BackgroundIn metazoans, Piwi-related Argonaute proteins play important roles in maintaining germline integrity and fertility and have been linked to a class of germline-enriched small RNAs termed piRNAs. Caenorhabditis elegans encodes two Piwi family proteins called PRG-1 and PRG-2, and PRG-1 interacts with the C. elegans piRNAs (21U-RNAs). Previous studies found that mutation of prg-1 causes a marked reduction in the expression of 21U-RNAs, temperature-sensitive defects in fertility and other phenotypic defects.ResultsIn this study, we wanted to systematically demonstrate the function of PRG-1 in the regulation of small RNAs and their targets. By analyzing small RNAs and mRNAs with and without a mutation in prg-1 during C. elegans development, we demonstrated that (1) mutation of prg-1 leads to a decrease in the expression of 21U-RNAs, and causes 35 ~ 40% of miRNAs to be down-regulated; (2) in C. elegans, approximately 3% (6% in L4) of protein-coding genes are differentially expressed after mutating prg-1, and 60 ~ 70% of these substantially altered protein-coding genes are up-regulated; (3) the target genes of the down-regulated miRNAs and the candidate target genes of the down-regulated 21U-RNAs are enriched in the up-regulated protein-coding genes; and (4) PRG-1 regulates protein-coding genes by down-regulating small RNAs (miRNAs and 21U-RNAs) that target genes that participate in the development of C. elegans.ConclusionsIn prg-1-mutated C. elegans, the expression of miRNAs and 21U-RNAs was reduced, and the protein-coding targets, which were associated with the development of C. elegans, were up-regulated. This may be the mechanism underlying PRG-1 function.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-321) contains supplementary material, which is available to authorized users.
Highlights
In metazoans, Piwi-related Argonaute proteins play important roles in maintaining germline integrity and fertility and have been linked to a class of germline-enriched small RNAs termed Piwi-interacting RNAs (piRNAs)
Loss of PRG-1 can cause germline defects and temperature-sensitive sterility [8,17]. 21U-RNAs, the piRNAs of C. elegans, are precisely 21 nucleotides long which are shorter than piRNAs in flies and mammals, have a bias for uracil 5′ monophosphate and have a modified 3′ end that resists periodate-degradation [7,8,18,19,20,21,22]. 21U-RNAs are expressed in the germline
High-throughput sequencing of small RNA samples produced 52,363,338 reads that mapped to the C. elegans genome
Summary
Piwi-related Argonaute proteins play important roles in maintaining germline integrity and fertility and have been linked to a class of germline-enriched small RNAs termed piRNAs. Caenorhabditis elegans encodes two Piwi family proteins called PRG-1 and PRG-2, and PRG-1 interacts with the C. elegans piRNAs (21U-RNAs). Small non-coding RNAs, including microRNAs (miRNAs), Piwi-interacting RNAs (piRNAs), endogenoussiRNAs (endo-siRNAs) and others, play important roles in controlling gene expression. These small RNAs interact with different types of Argonaute proteins to form complexes, such as the RNA-induced silencing complex (RISC) [1,2,3,4]. Mutation of prg-1 causes decreased expression of 21U-RNAs [8,17]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
