biostudies-literatureUnknown300(11)Che TJiangxi Provincial Natural Science FoundationKey Research and Development Program of Jiangxi ProvinceDouble Thousand Plan of Jiangxi ProvinceScience Fund for Distinguished Young Scholars of Jiangxi ProvinceNational Natural Science Foundation of ChinaGannan Medical UniversityThe hyperpolarization-activated cyclic nucleotide-gated (HCN) channels play a crucial role in regulating neuronal excitability. Despite growing evidence supporting the therapeutic potential of HCN1 inhibition in treating neurological disorders, the structural basis of channel inhibition by inhibitor has remained elusive. Here, we present the cryo-electron microscopy structure of human HCN1 channel in complex with inhibitor ivabradine, the drug on the market that acts on HCN channels. Combining electrophysiology, mutagenesis, and molecular dynamics simulations, our findings reveal that ivabradine binds to a previously unidentified pocket formed between the S4, S1, and HCN domain. Furthermore, through structure-based virtual screening, we identify two Food and Drug Administration-approved drThe Journal of biological chemistry107798https://www.ebi.ac.uk/biostudies/studies/S-EPMC11530593biostudies-literatureStructural mechanism of human HCN1 hyperpolarization-activated channel inhibition by ivabradine.PMC11530593Wan SLi JZhang JZhang MNan WCheng XZhang WZeng BChe TZhang YLv SXiong BYang TfalseStructural mechanism of human HCN1 hyperpolarization-activated channel inhibition by ivabradine.The hyperpolarization-activated cyclic nucleotide-gated (HCN) channels play a crucial role in regulating neuronal excitability. Despite growing evidence supporting the therapeutic potential of HCN1 inhibition in treating neurological disorders, the structural basis of channel inhibition by inhibitor has remained elusive. Here, we present the cryo-electron microscopy structure of human HCN1 channel in complex with inhibitor ivabradine, the drug on the market that acts on HCN channels. Combining electrophysiology, mutagenesis, and molecular dynamics simulations, our findings reveal that ivabradine binds to a previously unidentified pocket formed between the S4, S1, and HCN domain. Furthermore, through structure-based virtual screening, we identify two Food and Drug Administration-approved dr2024-01-01T00:00:00Z2024 Nov2026-06-01T06:53:06.335Z2025-04-06T14:25:10.41ZS-EPMC115305933930730910.1016/j.jbc.2024.107798