| RRC ID |
76000
|
| Author |
Liao S, Chen X, Xu T, Jin Q, Xu Z, Xu D, Zhou X, Zhu C, Guang S, Feng X.
|
| Title |
Antisense ribosomal siRNAs inhibit RNA polymerase I-directed transcription in C. elegans.
|
| Journal |
Nucleic Acids Res
|
| Abstract |
Eukaryotic cells express a wide variety of endogenous small regulatory RNAs that function in the nucleus. We previously found that erroneous rRNAs induce the generation of antisense ribosomal siRNAs (risiRNAs) which silence the expression of rRNAs via the nuclear RNAi defective (Nrde) pathway. To further understand the biological roles and mechanisms of this class of small regulatory RNAs, we conducted forward genetic screening to identify factors involved in risiRNA generation in Caenorhabditis elegans. We found that risiRNAs accumulated in the RNA exosome mutants. risiRNAs directed the association of NRDE proteins with pre-rRNAs and the silencing of pre-rRNAs. In the presence of risiRNAs, NRDE-2 accumulated in the nucleolus and colocalized with RNA polymerase I. risiRNAs inhibited the transcription elongation of RNA polymerase I by decreasing RNAP I occupancy downstream of the RNAi-targeted site. Meanwhile, exosomes mislocalized from the nucleolus to nucleoplasm in suppressor of siRNA (susi) mutants, in which erroneous rRNAs accumulated. These results established a novel model of rRNA surveillance by combining ribonuclease-mediated RNA degradation with small RNA-directed nucleolar RNAi system.
|
| Volume |
49(16)
|
| Pages |
9194-9210
|
| Published |
2021-9-20
|
| DOI |
10.1093/nar/gkab662
|
| PII |
6345473
|
| PMID |
34365510
|
| PMC |
PMC8450093
|
| MeSH |
Animals
Caenorhabditis elegans
Cell Nucleolus / metabolism
DNA-Directed RNA Polymerases / metabolism
Exosomes / genetics
Exosomes / metabolism
Gene Silencing
Mutation
RNA, Ribosomal / genetics
RNA, Ribosomal / metabolism*
RNA, Small Interfering / genetics
RNA, Small Interfering / metabolism*
Transcription Elongation, Genetic*
|
| Resource |
| C.elegans |
tm6653
tm6844
tm5568 |
