{"doi":"10.1016/j.jbc.2024.107249","title":"Key roles for phosphorylation and the Coiled-coil domain in TRIM56-mediated positive regulation of TLR3-TRIF–dependent innate immunity","abstract":"Tripartite-motif protein-56 (TRIM56) positively regulates the induction of type I interferon (IFN) response via the TLR3 pathway by enhancing IRF3 activation and depends on its C-terminal residues 621-750 for interacting with the adaptor TRIF. However, the precise underlying mechanism and detailed TRIM56 determinants remain unclear. Herein, we show ectopic expression of murine TRIM56 also enhances TLR3-dependent IFN-β promoter activation, suggesting functional conservation. We found that endogenous TRIM56 and TRIF formed a complex early (0.5-2 h) after poly-I:C stimulation and that TRIM56 overexpression also promoted activation of NF-κB by poly-I:C but not that by TNF-α or IL-1β, consistent with a specific effect on TRIF prior to the bifurcation of NF-κB and IRF3. Using transient transfection and Tet-regulated cell lines expressing various TRIM56 mutants, we demonstrated the Coiled-coil domain and a segment spanning residues ∼434-610, but not the B-box or residues 355-433, were required for TRIM56 augmentation of TLR3 signaling. Moreover, alanine substitution at each putative phosphorylation site, Ser 471 , Ser 475 and Ser 710 , abrogated TRIM56 function. Concordantly, mutants bearing Ser 471 Ala, Ser 475 Ala, or Ser 710 Ala, or lacking the Coiled-coil domain, all lost the capacity to enhance poly-I:C-induced establishment of an antiviral state. Furthermore, the Ser 710 Ala mutation disrupted the TRIM56-TRIF association. Using phospho-specific antibodies, we detected biphasic phosphorylation of TRIM56 at Ser 471 and Ser 475 following TLR3 stimulation, with the early phase occurring at ∼0.5-1 h, prior to IRF3 phosphorylation. Together, these data reveal novel molecular details critical for the TRIM56 augmentation of TLR3-dependent antiviral response and highlight important roles for TRIM56 scaffolding and phosphorylation.","journal":"Journal of Biological Chemistry","year":2024,"id":420227,"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":35,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9534,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1211640,"name":"Nan L. Li","orcid":null,"position":1,"is_corresponding":false},{"id":544329,"name":"Ruixue Wang","orcid":"0000-0002-8772-4954","position":2,"is_corresponding":false},{"id":410862,"name":"Xiaofan Li","orcid":"0000-0003-4168-0068","position":3,"is_corresponding":false},{"id":1211091,"name":"Z Li","orcid":"0009-0000-4254-7416","position":4,"is_corresponding":false},{"id":353267,"name":"Tony N. Marion","orcid":"0000-0001-6570-7179","position":5,"is_corresponding":false},{"id":308609,"name":"Kui Li","orcid":"0000-0002-2413-6020","position":6,"is_corresponding":false},{"id":308608,"name":"Baoming Liu","orcid":"0000-0003-1225-9936","position":0,"is_corresponding":true}],"reference_count":54,"raw_metadata":null,"created_at":"2026-07-19T01:57:25.777459Z","pmid":"38556084","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":[]}