{"doi":"10.1128/mbio.00852-23","title":"RecJ3/4-aRNase J form a Ubl-associated nuclease complex functioning in survival against DNA damage in <i>Haloferax volcanii</i>","abstract":"Nucleases are strictly regulated and often localized in the cell to avoid the uncontrolled degradation of DNA and RNA. Here, a new type of nuclease complex, composed of RecJ3, RecJ4, and aRNase J, was identified through its ATP-dependent association with the ubiquitin-like SAMP1 and AAA-ATPase Cdc48a. The complex was discovered in Haloferax volcanii , an archaeon lacking an RNA exosome. Genetic analysis revealed aRNase J to be essential and RecJ3, RecJ4, and Cdc48a to function in the recovery from DNA damage including genotoxic agents that generate double-strand breaks. The RecJ3:RecJ4:aRNase J complex (isolated in 2:2:1 stoichiometry) functioned primarily as a 3′−5′ exonuclease in hydrolyzing RNA and ssDNA, with the mechanism non-processive for ssDNA. aRNase J could also be purified as a homodimer that catalyzed endoribonuclease activity and, thus, was not restricted to the 5′−3′ exonuclease activity typical of aRNase J homologs. Moreover, RecJ3 and RecJ4 could be purified as a 560-kDa subcomplex in equimolar subunit ratio with nuclease activities mirroring the full RecJ3/4-aRNase J complex. These findings prompted reconstitution assays that suggested RecJ3/4 could suppress, alter, and/or outcompete the nuclease activities of aRNase J. Based on the phenotypic results, this control mechanism of aRNase J by RecJ3/4 is not necessary for cell growth but instead appears important for DNA repair. IMPORTANCE Nucleases are critical for various cellular processes including DNA replication and repair. Here, a dynamic type of nuclease complex is newly identifiedidentifiedidentifiedin the archaeon Haloferax volcanii , which is missing the canonical RNA exosome. The complex, composed of RecJ3, RecJ4, and aRNase J, functions primarily as a 3′−5′ exonuclease and was discovered through its ATP-dependent association with the ubiquitin-like SAMP1 and Cdc48a. aRNase J alone forms a homodimer that has endonuclease function and, thus, is not restricted to 5′−3′ exonuclease activity typical of other aRNase J enzymes. RecJ3/4 appears to suppress, alter, and/or outcompete the nuclease activities of aRNase J. While aRNase J is essential for growth, RecJ3/4, Cdc48a, and SAMPs are important for recovery against DNA damage. These biological distinctions may correlate with the regulated nuclease activity of aRNase J in the RecJ3/4-aRNaseJ complex.","journal":"mBio","year":2023,"id":368113,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":4,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9539,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2023-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":512407,"name":"Swathi Dantuluri","orcid":"0000-0002-9923-1655","position":1,"is_corresponding":false},{"id":1126059,"name":"Shae Margulies","orcid":"0000-0002-2563-2843","position":2,"is_corresponding":false},{"id":1126060,"name":"Victoria Smith","orcid":"0000-0002-5897-8859","position":3,"is_corresponding":false},{"id":1126558,"name":"Rebecca Lever","orcid":null,"position":4,"is_corresponding":false},{"id":1126061,"name":"Thorsten Allers","orcid":"0000-0002-7308-3332","position":5,"is_corresponding":false},{"id":258513,"name":"Jin Koh","orcid":"0000-0002-5689-1530","position":6,"is_corresponding":false},{"id":258510,"name":"Sixue Chen","orcid":"0000-0002-6690-7612","position":7,"is_corresponding":false},{"id":345489,"name":"Julie A. Maupin‐Furlow","orcid":"0000-0001-6105-0923","position":8,"is_corresponding":false},{"id":483882,"name":"Huiyong Jia","orcid":null,"position":0,"is_corresponding":true}],"reference_count":122,"raw_metadata":null,"created_at":"2026-07-19T01:15:20.453499Z","pmid":"37458473","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}