{"doi":"10.1101/2024.08.30.610324","title":"SNARE disassembly requires Sec18/NSF side-loading","abstract":"SNARE proteins drive membrane fusion at different cell compartments as their core domains zipper into a parallel four-helix bundle. After fusion, these bundles are disassembled by the AAA+ protein Sec18/NSF and its adaptor Sec17/α-SNAP to make them available for subsequent rounds of membrane fusion. SNARE domains are often flanked by C-terminal transmembrane or N-terminal domains. Previous structures of the NSF-α-SNAP-SNARE complex revealed binding to the D1 ATPase pore, posing a topological constraint as SNARE transmembrane domains would prevent complete substrate threading as suggested for other AAA+ systems. Using mass-spectrometry in yeast cells, we show N-terminal SNARE domain interactions with Sec18, exacerbating this topological issue. We present cryo-EM structures of a yeast SNARE complex, Sec18, and Sec17 in a non-hydrolyzing condition, which show SNARE Sso1 threaded through the D1 and D2 ATPase rings of Sec18, with its folded, N-terminal Habc domain interacting with the D2 ring. This domain does not unfold during Sec18/NSF activity. Cryo-EM structures under hydrolyzing conditions revealed substrate-released and substrate-free states of Sec18 with a coordinated opening in the side of the ATPase rings. Thus, Sec18/NSF operates by substrate side-loading and unloading topologically constrained SNARE substrates.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2024,"id":486337,"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":0.9434,"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":299250,"name":"K. Ian White","orcid":"0000-0001-8182-3655","position":1,"is_corresponding":false},{"id":51694,"name":"Richard A. Pfuetzner","orcid":"0000-0002-1741-2330","position":2,"is_corresponding":false},{"id":1218652,"name":"Bharti Singal","orcid":"0000-0002-9482-5251","position":3,"is_corresponding":false},{"id":299248,"name":"Luis Esquivies","orcid":"0000-0002-1750-6775","position":4,"is_corresponding":false},{"id":1330119,"name":"Garvey Mckenzie","orcid":null,"position":5,"is_corresponding":false},{"id":1329748,"name":"Fang Liu","orcid":"0000-0002-1780-1723","position":6,"is_corresponding":false},{"id":1330120,"name":"Katherine DeLong","orcid":null,"position":7,"is_corresponding":false},{"id":568732,"name":"Ucheor B. Choi","orcid":"0000-0003-1541-2967","position":8,"is_corresponding":false},{"id":693237,"name":"Elizabeth Montabana","orcid":null,"position":9,"is_corresponding":false},{"id":1267064,"name":"Theresa McLaughlin","orcid":null,"position":10,"is_corresponding":false},{"id":353607,"name":"William Wickner","orcid":"0000-0001-8431-0468","position":11,"is_corresponding":false},{"id":57565,"name":"Axel T. Brünger","orcid":"0000-0001-5121-2036","position":12,"is_corresponding":false},{"id":59641,"name":"Yousuf A. Khan","orcid":"0000-0003-0201-2796","position":0,"is_corresponding":true}],"reference_count":66,"raw_metadata":null,"created_at":"2026-07-19T02:07:57.049469Z","pmid":"39257774","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":[]}