Wang Y, Weng C, Chen X, Zhou X, Huang X, Yan Y, Zhu C. CDE-1 suppresses the production of risiRNA by coupling polyuridylation and degradation of rRNA.
BMC Biol 2020;
18:115. [PMID:
32887607 PMCID:
PMC7472701 DOI:
10.1186/s12915-020-00850-z]
[Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 08/17/2020] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND
Modification of RNAs, particularly at the terminals, is critical for various essential cell processes; for example, uridylation is implicated in tumorigenesis, proliferation, stem cell maintenance, and immune defense against viruses and retrotransposons. Ribosomal RNAs can be regulated by antisense ribosomal siRNAs (risiRNAs), which downregulate pre-rRNAs through the nuclear RNAi pathway in Caenorhabditis elegans. However, the biogenesis and regulation of risiRNAs remain obscure. Previously, we showed that 26S rRNAs are uridylated at the 3'-ends by an unknown terminal polyuridylation polymerase before the rRNAs are degraded by a 3' to 5' exoribonuclease SUSI-1(ceDIS3L2).
RESULTS
Here, we found that CDE-1, one of the three C.elegans polyuridylation polymerases (PUPs), is specifically involved in suppressing risiRNA production. CDE-1 localizes to perinuclear granules in the germline and uridylates Argonaute-associated 22G-RNAs, 26S, and 5.8S rRNAs at the 3'-ends. Immunoprecipitation followed by mass spectrometry (IP-MS) revealed that CDE-1 interacts with SUSI-1(ceDIS3L2). Consistent with these results, both CDE-1 and SUSI-1(ceDIS3L2) are required for the inheritance of RNAi.
CONCLUSIONS
This work identified a rRNA surveillance machinery of rRNAs that couples terminal polyuridylation and degradation.
Collapse