Cingulin regulates hair cell cuticular plate morphology and is required for hearing in human and mouse
Guang‐Jie Zhu, Yuhang Huang, Linqing Zhang, Keji Yan, Cui Qiu, Yihan He, Qing Liu, Chengwen Zhu, Matías Morin, Miguel A. Moreno‐Pelayo, Min‐Sheng Zhu, Xin Cao, Han Zhou, Xiaoyun Qian, Zhigang Xu, Jie Chen, Xia Gao, Guoqiang Wan
Abstract
Cingulin (CGN) is a cytoskeleton-associated protein localized at the apical junctions of epithelial cells. CGN interacts with major cytoskeletal filaments and regulates RhoA activity. However, physiological roles of CGN in development and human diseases are currently unknown. Here, we report a multi-generation family presenting with autosomal dominant non-syndromic hearing loss (ADNSHL) that co-segregates with a CGN heterozygous truncating variant, c.3330delG (p.Leu1110Leufs*17). CGN is normally expressed at the apical cell junctions of the organ of Corti, with enriched localization at hair cell cuticular plates and circumferential belts. In mice, the putative disease-causing mutation results in reduced expression and abnormal subcellular localization of the CGN protein, abolishes its actin polymerization activity, and impairs the normal morphology of hair cell cuticular plates and hair bundles. Hair cell-specific Cgn knockout leads to high-frequency hearing loss. Importantly, Cgn mutation knockin mice display noise-sensitive, progressive hearing loss and outer hair cell degeneration. In summary, we identify CGN c.3330delG as a pathogenic variant for ADNSHL and reveal essential roles of CGN in the maintenance of cochlear hair cell structures and auditory function.