{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T18:30:35Z","timestamp":1793039435492,"version":"4.5.0"},"reference-count":27,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T00:00:00Z","timestamp":1765411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002426","name":"Fondazione Telethon","doi-asserted-by":"publisher","award":["GMR24T1046"],"award-info":[{"award-number":["GMR24T1046"]}],"id":[{"id":"10.13039\/501100002426","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Fondazione Telethon\/Cariplo","award":["GJC22008"],"award-info":[{"award-number":["GJC22008"]}]},{"name":"D34 Health","award":["CUP B53C22006100001"],"award-info":[{"award-number":["CUP B53C22006100001"]}]},{"name":"Italian PNRR project MNESYS","award":["RONEND"],"award-info":[{"award-number":["RONEND"]}]},{"name":"Italian Ministry of Foreign Affairs","award":["SE24GR07"],"award-info":[{"award-number":["SE24GR07"]}]},{"name":"MUR","award":["RBAP11ETKA-005"],"award-info":[{"award-number":["RBAP11ETKA-005"]}]},{"name":"European Union\u2014NextGenerationEU (Missione 4 Componente 2, \u201cDalla ricerca all\u2019impresa\u201d, Innovation Ecosystem RAISE \u201cRobotics and AI for Socio-economic Empowerment\u201d","award":["ECS00000035"],"award-info":[{"award-number":["ECS00000035"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Variants in CLCN3 and CLCN4, encoding the neuronal endosomal Cl\u2212\/H+ antiporters ClC-3 and ClC-4, are linked to neurodevelopmental disorders with broad phenotypic variability. Over sixty CLCN4 variants have been functionally characterized, showing gain- or loss-of-function (GoF or LoF) effects. While ClC-3 can function as a homodimer, ClC-4 depends on heterodimerization with ClC-3 for efficient endosomal trafficking. CLCN4, located on the X chromosome, exhibits diverse pathogenic outcomes: complete LoF variants often cause non-syndromic presentations in hemizygous males and are asymptomatic in heterozygous females, whereas certain missense variants with partial or complete LoF produce severe syndromic phenotypes in both sexes. Here, we demonstrate dominant effects of three CLCN4 variants within ClC-3\/ClC-4 heterodimers using two-electrode voltage-clamp recordings in Xenopus laevis oocytes and whole-cell patch-clamp recordings in mammalian cells co-expressing both proteins via a bicistronic IRES construct. Our findings provide the first evidence of dominant-negative CLCN4 effects within ClC-3\/ClC-4 complexes and establish a platform for functional analysis of additional disease-associated variants.<\/jats:p>","DOI":"10.3390\/cells14241973","type":"journal-article","created":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T12:57:41Z","timestamp":1765457861000},"page":"1973","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Dominant Action of CLCN4 Neurodevelopmental Disease Variants in Heteromeric Endosomal ClC-3\/ClC-4 Transporters"],"prefix":"10.3390","volume":"14","author":[{"given":"Abraham","family":"Tettey-Matey","sequence":"first","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2980-7951","authenticated-orcid":false,"given":"Alessandra","family":"Picollo","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"Sbrana","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8627-4421","authenticated-orcid":false,"given":"Maria Antonietta","family":"Coppola","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eugenia","family":"Rubino","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3497-8775","authenticated-orcid":false,"given":"Alice","family":"Giusto","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4990-7554","authenticated-orcid":false,"given":"Margherita","family":"Festa","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4774-2223","authenticated-orcid":false,"given":"Elena","family":"Angeli","sequence":"additional","affiliation":[{"name":"DIFI Lab, Dipartimento di Fisica, Universit\u00e0 di Genova, 16146 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6512-1802","authenticated-orcid":false,"given":"Cristiana","family":"Picco","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raffaella","family":"Barbieri","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paola","family":"Gavazzo","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8644-8847","authenticated-orcid":false,"given":"Michael","family":"Pusch","sequence":"additional","affiliation":[{"name":"Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy"},{"name":"DIFI Lab, Dipartimento di Fisica, Universit\u00e0 di Genova, 16146 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"642","DOI":"10.1038\/s41562-023-01530-y","article-title":"A meta-analysis of genetic effects associated with neurodevelopmental disorders and co-occurring conditions","volume":"7","author":"Gidziela","year":"2023","journal-title":"Nat. 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Rev."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"e103358","DOI":"10.15252\/embj.2019103358","article-title":"Uncoupling endosomal CLC chloride\/proton exchange causes severe neurodegeneration","volume":"39","author":"Weinert","year":"2020","journal-title":"EMBO J."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Coppola, M.A., Tettey-Matey, A., Imbrici, P., Gavazzo, P., Liantonio, A., and Pusch, M. (2023). Biophysical Aspects of Neurodegenerative and Neurodevelopmental Disorders Involving Endo-\/Lysosomal CLC Cl\u2212\/H+ Antiporters. Life, 13.","DOI":"10.3390\/life13061317"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Bose, S., He, H., and Stauber, T. (2021). Neurodegeneration Upon Dysfunction of Endosomal\/Lysosomal CLC Chloride Transporters. Front. Cell Dev. 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