{"doi":"10.1093/nar/gkae138","title":"Structural insights into the N-terminal APHB domain of HrpA: mediating canonical and i-motif recognition","abstract":"RNA helicases function as versatile enzymes primarily responsible for remodeling RNA secondary structures and organizing ribonucleoprotein complexes. In our study, we conducted a systematic analysis of the helicase-related activities of Escherichia coli HrpA and presented the structures of both its apo form and its complex bound with both conventional and non-canonical DNAs. Our findings reveal that HrpA exhibits NTP hydrolysis activity and binds to ssDNA and ssRNA in distinct sequence-dependent manners. While the helicase core plays an essential role in unwinding RNA/RNA and RNA/DNA duplexes, the N-terminal extension in HrpA, consisting of three helices referred to as the APHB domain, is crucial for ssDNA binding and RNA/DNA duplex unwinding. Importantly, the APHB domain is implicated in binding to non-canonical DNA structures such as G-quadruplex and i-motif, and this report presents the first solved i-motif-helicase complex. This research not only provides comprehensive insights into the multifaceted roles of HrpA as an RNA helicase but also establishes a foundation for further investigations into the recognition and functional implications of i-motif DNA structures in various biological processes.","journal":"Nucleic Acids Research","year":2024,"id":467387,"datarank":0.2658913062667005,"base_score":1.3862943611198906,"endowment":1.3862943611198906,"self_citation_contribution":0.20794415416798362,"citation_network_contribution":0.05794715209871688,"self_endowment_contribution":0.20794415416798362,"citer_contribution":0.05794715209871688,"corpus_percentile":null,"corpus_rank":null,"citation_count":3,"citer_count":3,"citers_with_citation_signal":2,"citers_with_endowment":2,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.953,"is_data_producer":true,"deposit_databanks":{"PDB":["8PO7","8PO6","8PO8"]},"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":1299772,"name":"Lingyun Huang","orcid":"0000-0002-0561-1615","position":1,"is_corresponding":false},{"id":1300131,"name":"Ling-Gang Yuan","orcid":null,"position":2,"is_corresponding":false},{"id":1300132,"name":"Na-Nv Liu","orcid":null,"position":3,"is_corresponding":false},{"id":1300133,"name":"Hai‐Hong Li","orcid":null,"position":4,"is_corresponding":false},{"id":1300134,"name":"Xia Ai","orcid":null,"position":5,"is_corresponding":false},{"id":459427,"name":"Dongsheng Lei","orcid":"0000-0003-1640-0693","position":6,"is_corresponding":false},{"id":1299773,"name":"Xi‐Miao Hou","orcid":"0000-0003-3499-443X","position":7,"is_corresponding":false},{"id":1162426,"name":"S. Réty","orcid":"0000-0002-2089-6727","position":8,"is_corresponding":false},{"id":1299774,"name":"Xu‐Guang Xi","orcid":"0000-0002-2117-1066","position":9,"is_corresponding":false},{"id":1300130,"name":"Ben-Ge Xin","orcid":null,"position":0,"is_corresponding":true}],"reference_count":52,"raw_metadata":null,"created_at":"2026-07-19T02:05:10.907983Z","pmid":"38412313","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":[]}