RRC ID 76168
Author Fasimoye RY, Spencer REB, Soto-Martin E, Eijlers P, Elmassoudi H, Brivio S, Mangana C, Sabele V, Rechtorikova R, Wenzel M, Connolly B, Pettitt J, Müller B.
Title A novel, essential trans-splicing protein connects the nematode SL1 snRNP to the CBC-ARS2 complex.
Journal Nucleic Acids Res
Abstract Spliced leader trans-splicing is essential for gene expression in many eukaryotes. To elucidate the molecular mechanism of this process, we characterise the molecules associated with the Caenorhabditis elegans major spliced leader snRNP (SL1 snRNP), which donates the spliced leader that replaces the 5' untranslated region of most pre-mRNAs. Using a GFP-tagged version of the SL1 snRNP protein SNA-1 created by CRISPR-mediated genome engineering, we immunoprecipitate and identify RNAs and protein components by RIP-Seq and mass spectrometry. This reveals the composition of the SL1 snRNP and identifies associations with spliceosome components PRP-8 and PRP-19. Significantly, we identify a novel, nematode-specific protein required for SL1 trans-splicing, which we designate SNA-3. SNA-3 is an essential, nuclear protein with three NADAR domains whose function is unknown. Mutation of key residues in NADAR domains inactivates the protein, indicating that domain function is required for activity. SNA-3 interacts with the CBC-ARS2 complex and other factors involved in RNA metabolism, including SUT-1 protein, through RNA or protein-mediated contacts revealed by yeast two-hybrid assays, localisation studies and immunoprecipitations. Our data are compatible with a role for SNA-3 in coordinating trans-splicing with target pre-mRNA transcription or in the processing of the Y-branch product of the trans-splicing reaction.
Volume 50(13)
Pages 7591-7607
Published 2022-7-22
DOI 10.1093/nar/gkac534
PII 6613924
PMID 35736244
PMC PMC9303266
MeSH 5' Untranslated Regions Animals Caenorhabditis elegans* / genetics Caenorhabditis elegans* / metabolism Caenorhabditis elegans Proteins* / metabolism Nuclear Proteins* / metabolism RNA Splicing RNA, Helminth* / genetics RNA, Spliced Leader* / genetics Ribonucleoproteins, Small Nuclear / genetics Trans-Splicing*
C.elegans tm2956