{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Desotell A"],"funding":["NIH","NIH HHS","NIGMS NIH HHS"],"pagination":["gkaf1442"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC12774660"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["54(1)"],"pubmed_abstract":["The U7 snRNP (small nuclear ribonucleoprotein) is responsible for the 3'-end processing of replication-dependent histone messenger RNA precursors (pre-mRNAs). A helix in the Lsm11 N-terminal extension contacts the metallo-β-lactamase domain of the U7 snRNP endonuclease CPSF73. We mutated or deleted this helix and found that the mutant machineries had substantially reduced cleavage activity toward the pre-mRNA. Our cryo-electron microscopy (cryo-EM) studies indicated that the helix was important for helping to hold CPSF73 in its correct position for the cleavage reaction. We also reconstituted a wild-type U7 snRNP in complex with a methylated, noncleavable pre-mRNA. We observed that CPSF73 could achieve an open conformation independent of RNA binding to its active site. Finally, we found th"],"journal":["Nucleic acids research"],"pubmed_title":["An N-terminal helix of Lsm11 stabilizes CPSF73 in U7 snRNP for histone pre-mRNA 3'-end processing."],"pmcid":["PMC12774660"],"funding_grant_id":["R35 GM118093","R35GM118093"],"pubmed_authors":["Marzluff WF","Tong L","Dominski Z","Desotell A"],"additional_accession":[]},"is_claimable":false,"name":"An N-terminal helix of Lsm11 stabilizes CPSF73 in U7 snRNP for histone pre-mRNA 3'-end processing.","description":"The U7 snRNP (small nuclear ribonucleoprotein) is responsible for the 3'-end processing of replication-dependent histone messenger RNA precursors (pre-mRNAs). A helix in the Lsm11 N-terminal extension contacts the metallo-β-lactamase domain of the U7 snRNP endonuclease CPSF73. We mutated or deleted this helix and found that the mutant machineries had substantially reduced cleavage activity toward the pre-mRNA. Our cryo-electron microscopy (cryo-EM) studies indicated that the helix was important for helping to hold CPSF73 in its correct position for the cleavage reaction. We also reconstituted a wild-type U7 snRNP in complex with a methylated, noncleavable pre-mRNA. We observed that CPSF73 could achieve an open conformation independent of RNA binding to its active site. Finally, we found th","dates":{"release":"2026-01-01T00:00:00Z","publication":"2026 Jan","modification":"2026-07-15T09:12:48.928Z","creation":"2026-07-02T03:08:59.707Z"},"accession":"S-EPMC12774660","cross_references":{"pubmed":["41495886"],"doi":["10.1093/nar/gkaf1442"]}}