{"doi":"10.1016/j.jbc.2024.107465","title":"The proteostasis interactomes of trafficking-deficient variants of the voltage-gated potassium channel KV11.1 associated with long QT syndrome","abstract":"The voltage-gated potassium ion channel K V 11.1 plays a critical role in cardiac repolarization. Genetic variants that render Kv11.1 dysfunctional cause long QT syndrome (LQTS), which is associated with fatal arrhythmias. Approximately 90% of LQTS-associated variants cause intracellular protein transport (trafficking) dysfunction, which pharmacological chaperones like E-4031 can rescue. Protein folding and trafficking decisions are regulated by chaperones, protein quality control factors, and trafficking machinery comprising the cellular proteostasis network. Here, we test whether trafficking dysfunction is associated with alterations in the proteostasis network of pathogenic Kv11.1 variants and whether pharmacological chaperones can normalize the proteostasis network of responsive variants. We used affinity-purification coupled with tandem mass tag–based quantitative mass spectrometry to assess protein interaction changes of WT K V 11.1 or trafficking-deficient channel variants in the presence or absence of E-4031. We identified 572 core K V 11.1 protein interactors. Trafficking-deficient variants K V 11.1-G601S and K V 11.1-G601S-G965 ∗ had significantly increased interactions with proteins responsible for folding, trafficking, and degradation compared to WT. We confirmed previous findings that the proteasome is critical for K V 11.1 degradation. Our report provides the first comprehensive characterization of protein quality control mechanisms of K V 11.1. We find extensive interactome remodeling associated with trafficking-deficient K V 11.1 variants and with pharmacological chaperone rescue of K V 11.1 cell surface expression. The identified protein interactions could be targeted therapeutically to improve K V 11.1 trafficking and treat LQTS.","journal":"Journal of Biological Chemistry","year":2024,"id":448773,"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":5,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9609,"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":1268159,"name":"Lea A. Barny","orcid":null,"position":1,"is_corresponding":false},{"id":1106792,"name":"Tri Q.","orcid":"0009-0007-8370-2823","position":2,"is_corresponding":false},{"id":266531,"name":"Eli Fritz McDonald","orcid":"0000-0002-0572-330X","position":3,"is_corresponding":false},{"id":236808,"name":"Björn C. Knollmann","orcid":"0000-0003-4956-9735","position":4,"is_corresponding":false},{"id":249875,"name":"Lars Plate","orcid":"0000-0003-4363-6116","position":5,"is_corresponding":false},{"id":955940,"name":"Christian Egly","orcid":"0000-0002-1755-7142","position":0,"is_corresponding":true}],"reference_count":63,"raw_metadata":null,"created_at":"2026-07-19T02:02:12.215092Z","pmid":"38876300","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":[]}