{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:28:14Z","timestamp":1785414494272,"version":"3.56.0"},"reference-count":33,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T00:00:00Z","timestamp":1779408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82271167"],"award-info":[{"award-number":["82271167"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["82271167"],"award-info":[{"award-number":["82271167"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Top-notch Project of Shanghai Oriental Talents Program"},{"name":"Leadership Project of Chunshen Pyramid Talents Program"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Hereditary sensorineural hearing loss (SNHL) represents a significant global public health burden. DFNX2, an X-linked form of non-syndromic SNHL, is caused by pathogenic variants in the POU3F4 gene. This study aimed to identify a novel POU3F4 mutation and characterize its functional consequences to elucidate the molecular pathogenesis of DFNX2. A three-generation Chinese family with X-linked deafness was recruited. Targeted next-generation sequencing was used to screen candidate variants, which were validated by Sanger sequencing for co-segregation analysis. Functional assays, including subcellular localization, dual-luciferase reporter assay, Western blotting, and homology modeling, were performed to assess the mutation\u2019s effects. A novel frameshift mutation, c.670_673dupGGTA (p.(Asn225Argfs*2)), was identified and showed complete co-segregation with the deafness phenotype. The mutant protein exhibited cytoplasmic mislocalization, and dual-luciferase assays revealed a severe reduction in transcriptional activation capacity, whereas Western blot confirmed stable expression of the truncated protein. Structural modeling predicted the loss of both the POUS and POUH DNA-binding subdomains. Collectively, this study expands the mutational spectrum of POU3F4 and supports previously reported mechanisms underlying DFNX2 pathogenesis.<\/jats:p>","DOI":"10.3390\/life16060868","type":"journal-article","created":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T06:42:18Z","timestamp":1779691338000},"page":"868","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Identification and Functional Characterization of a Novel POU3F4 Frameshift Mutation in a Chinese Family"],"prefix":"10.3390","volume":"16","author":[{"given":"Shuwen","family":"Fan","sequence":"first","affiliation":[{"name":"ENT Institute, Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China"},{"name":"NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yaqiong","family":"Guan","sequence":"additional","affiliation":[{"name":"Department of Medical Technology and Information Engineering, Zhejiang Chinese Medical University, Hangzhou 310053, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengya","family":"Xiang","sequence":"additional","affiliation":[{"name":"ENT Institute, Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China"},{"name":"NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongzhe","family":"Yu","sequence":"additional","affiliation":[{"name":"ENT Institute, Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China"},{"name":"NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tianyang","family":"Zhang","sequence":"additional","affiliation":[{"name":"ENT Institute, Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China"},{"name":"NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jialei","family":"Fu","sequence":"additional","affiliation":[{"name":"ENT Institute, Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China"},{"name":"NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahao","family":"Fei","sequence":"additional","affiliation":[{"name":"Department of Medical Technology and Information Engineering, Zhejiang Chinese Medical University, Hangzhou 310053, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6295-7455","authenticated-orcid":false,"given":"Yongtao","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Medical Technology and Information Engineering, Zhejiang Chinese Medical University, Hangzhou 310053, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3477-1562","authenticated-orcid":false,"given":"Yunfeng","family":"Wang","sequence":"additional","affiliation":[{"name":"ENT Institute, Department of Otorhinolaryngology, EYE & ENT Hospital, Fudan University, Shanghai 200031, China"},{"name":"NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1016\/S1525-1578(10)60522-3","article-title":"Hereditary non-syndromic sensorineural hearing loss: Transforming silence to sound","volume":"6","author":"Schrijver","year":"2004","journal-title":"J. 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