{"doi":"10.1101/2025.08.30.673144","title":"Inhibition of Ca <sub>V</sub> 1.4 channels by Ca <sub>V</sub> 3 channel antagonists ML218 and Z944","abstract":"ABSTRACT Among the three classes of voltage-gated Ca 2+ channels (Ca v 1, Ca v 2, Ca v 3), Ca v 3 T-type channels are drug targets for disorders including epilepsy and pain. Antagonists such as Z944 and ML218 are highly selective for Ca v 3 compared to the Ca v 1.2 L-type channel but whether they have additional activity on other Ca v 1 subtypes is unknown. Here, we investigated the effects of Z944 and ML218 on the Ca v 1.4 channel which regulates neurotransmitter release from retinal photoreceptors. In HEK293T cells transfected with Ca v 1.4 and the auxiliary β 2×13 and α 2 δ-4 subunits, Z944 and ML218 inhibited Ca 2+ currents with IC 50 values of ∼30 µM and 2 µM, respectively. Structure-based modeling combined with functional studies revealed the importance of a cluster of methionine residues, particularly M1004, within the DHP binding site for the effects of ML218. Compared to mutation of a conserved threonine (T1007) that is required for DHP sensitivity of Ca v 1 channels, mutation of M1004 had a 10-fold greater impact in diminishing the potency of ML218. Ca v 1.2 was significantly less sensitive to ML218 inhibition (IC 50 ∼ 37 µM) than Ca v 1.4, which could not be attributed to a valine in place of M1004 in Ca v 1.2. We conclude that ML218 and Z944 are dual Ca v 1/Ca v 3 modulators of Ca V 1.4 and should be used with caution when dissecting the contributions of Ca V 3 channels in tissues where Ca v 1.4 is expressed.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2025,"id":574026,"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":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9611,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1447974,"name":"Juan de la Rosa Vázquez","orcid":"0000-0002-6266-5919","position":1,"is_corresponding":false},{"id":1280817,"name":"Adriana Hernández González","orcid":"0000-0002-6251-5136","position":2,"is_corresponding":false},{"id":249827,"name":"Vladimir Yarov‐Yarovoy","orcid":"0000-0002-2325-4834","position":3,"is_corresponding":false},{"id":607694,"name":"Amy Lee","orcid":"0000-0001-8021-0443","position":4,"is_corresponding":false},{"id":1481525,"name":"Jinglang Sun","orcid":null,"position":0,"is_corresponding":true}],"reference_count":64,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T02:57:36.753600Z","pmid":null,"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":[]}