Wan Yining, Li Jinqiu, Guo Yingyuan, Guo Fang, Zhao Ying, Li Yue, Yang Xia, Chen Huidan, Xie Shimin, Wang Mingyong, Guan Guofang, Zhu Yilong, Li Xiao
Department of Otolaryngology, The Second Hospital of Jilin University, Changchun, Jilin, China.
Academicians Workstation of Jilin Province, Changchun University of Chinese Medicine, Changchun, Jilin, China.
Hum Mutat. 2025 Feb 14;2025:6690588. doi: 10.1155/humu/6690588. eCollection 2025.
The study was aimed at identifying the pathogenic gene responsible for X-linked nonsyndromic hearing loss (NSHL) in a five-generation Chinese family and at elucidating the gene's function both in vivo using a zebrafish model and in vitro using PRPS1 knockdown HEI-OC1 cells. Exome sequencing (ES) and Sanger sequencing were used to identify the pathogenic variants. A transgenic zebrafish model overexpressing the novel PRPS1 variant (c.494G>A: p.Cys165Tyr) was constructed, and PRPS1 was knocked down in HEI-OC1 cells using siRNA to explore the underlying mechanisms. Hair cell development and behavior were assessed in zebrafish, and mitochondrial function and cell viability were analyzed in HEI-OC1 cells. A novel missense variant (c.494G>A: p.Cys165Tyr) in the PRPS1 gene was identified as the pathogenic variant causing progressive X-linked deafness-1 (DFNX1). The variant led to hair cell death in zebrafish, with disrupted swimming behavior. In HEI-OC1 cells, PRPS1 knockdown resulted in downregulation of the nicotinamide adenine dinucleotide (NAD)/sirtuin 3 (SIRT3)/superoxide dismutase 2 (SOD2) pathway, increased reactive oxygen species (ROS) accumulation, mitochondrial dysfunction, and apoptosis, which were partially rescued by pretreatment with nicotinamide mononucleotide (NMN), a precursor of NAD. The study reports a novel PRPS1 variant contributing to the variant spectrum of PRPS1 and highlights the role of PRPS1 deficiency in increasing oxidative stress-induced hair cell apoptosis via the NAD/SIRT3/SOD2 pathway. These findings provide new insights into the molecular mechanisms of PRPS1-related hearing loss and potential therapeutic targets.
该研究旨在确定一个五代中国家系中导致X连锁非综合征性听力损失（NSHL）的致病基因，并通过斑马鱼模型在体内以及使用PRPS1基因敲低的HEI-OC1细胞在体外阐明该基因的功能。采用外显子组测序（ES）和桑格测序来鉴定致病变异。构建了过表达新型PRPS1变体（c.494G>A：p.Cys165Tyr）的转基因斑马鱼模型，并使用小干扰RNA（siRNA）在HEI-OC1细胞中敲低PRPS1以探究潜在机制。评估斑马鱼的毛细胞发育和行为，并分析HEI-OC1细胞中的线粒体功能和细胞活力。PRPS1基因中的一个新型错义变体（c.494G>A：p.Cys165Tyr）被鉴定为导致进行性X连锁耳聋-1（DFNX1）的致病变异。该变体导致斑马鱼毛细胞死亡，并伴有游泳行为紊乱。在HEI-OC1细胞中，PRPS1基因敲低导致烟酰胺腺嘌呤二核苷酸（NAD）/沉默调节蛋白3（SIRT3）/超氧化物歧化酶2（SOD2）通路下调，活性氧（ROS）积累增加、线粒体功能障碍和细胞凋亡，而烟酰胺单核苷酸（NMN，一种NAD前体）预处理可部分挽救这些情况。该研究报告了一个新的PRPS1变体，丰富了PRPS1的变体表型谱，并强调了PRPS1缺乏通过NAD/SIRT3/SOD2途径增加氧化应激诱导的毛细胞凋亡中的作用。这些发现为PRPS1相关听力损失的分子机制和潜在治疗靶点提供了新见解。
