Mutations of MAP1B encoding a microtubule-associated phosphoprotein cause sensorineural hearing loss

Bibliographic Details
Title: Mutations of MAP1B encoding a microtubule-associated phosphoprotein cause sensorineural hearing loss
Authors: Limei Cui, Jing Zheng, Qiong Zhao, Jia-Rong Chen, Hanqing Liu, Guanghua Peng, Yue Wu, Chao Chen, Qiufen He, Haosong Shi, Shankai Yin, Rick A. Friedman, Ye Chen, Min-Xin Guan
Source: JCI Insight, Vol 5, Iss 23 (2020)
Publisher Information: American Society for Clinical investigation, 2020.
Publication Year: 2020
Collection: LCC:Medicine
Subject Terms: Genetics, Otology, Medicine
More Details: The pathophysiology underlying spiral ganglion cell defect–induced deafness remains elusive. Using the whole exome sequencing approach, in combination with functional assays and a mouse disease model, we identified the potentially novel deafness-causative MAP1B gene encoding a highly conserved microtubule-associated protein. Three novel heterozygous MAP1B mutations (c.4198A>G, p.1400S>G; c.2768T>C, p.923I>T; c.5512T>C, p.1838F>L) were cosegregated with autosomal dominant inheritance of nonsyndromic sensorineural hearing loss in 3 unrelated Chinese families. Here, we show that MAP1B is highly expressed in the spiral ganglion neurons in the mouse cochlea. Using otic sensory neuron–like cells, generated by pluripotent stem cells from patients carrying the MAP1B mutation and control subject, we demonstrated that the p.1400S>G mutation caused the reduced levels and deficient phosphorylation of MAP1B, which are involved in the microtubule stability and dynamics. Strikingly, otic sensory neuron–like cells exhibited disturbed dynamics of microtubules, axonal elongation, and defects in electrophysiological properties. Dysfunctions of these derived otic sensory neuron–like cells were rescued by genetically correcting MAP1B mutation using CRISPR/Cas9 technology. Involvement of MAP1B in hearing was confirmed by audiometric evaluation of Map1b heterozygous KO mice. These mutant mice displayed late-onset progressive sensorineural hearing loss that was more pronounced in the high frequencies. The spiral ganglion neurons isolated from Map1b mutant mice exhibited the deficient phosphorylation and disturbed dynamics of microtubules. Map1b deficiency yielded defects in the morphology and electrophysiology of spiral ganglion neurons, but it did not affect the morphologies of cochlea in mice. Therefore, our data demonstrate that dysfunctions of spiral ganglion neurons induced by MAP1B deficiency caused hearing loss.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2379-3708
Relation: https://doaj.org/toc/2379-3708
DOI: 10.1172/jci.insight.136046
Access URL: https://doaj.org/article/d7b9609d77224c7ba5b56f7c0d1119f2
Accession Number: edsdoj.7b9609d77224c7ba5b56f7c0d1119f2
Database: Directory of Open Access Journals
More Details
ISSN:23793708
DOI:10.1172/jci.insight.136046
Published in:JCI Insight
Language:English