THOC1 deficiency leads to late-onset nonsyndromic hearing loss through p53-mediated hair cell apoptosis

Luping Zhang; Yu Gao; Ru Zhang; Feifei Sun; Cheng Cheng; Fuping Qian; Xuchu Duan; Guanyun Wei; Cheng Sun; Xiuhong Pang; Penghui Chen; Renjie Chai; Tao Yang; Hao Wu; Dong Liu

doi:10.1371/journal.pgen.1008953

THOC1 deficiency leads to late-onset nonsyndromic hearing loss through p53-mediated hair cell apoptosis

PLoS Genet. 2020 Aug 10;16(8):e1008953. doi: 10.1371/journal.pgen.1008953. eCollection 2020 Aug.

Authors

Luping Zhang¹, Yu Gao¹, Ru Zhang², Feifei Sun¹, Cheng Cheng³, Fuping Qian^{1

3}, Xuchu Duan¹, Guanyun Wei¹, Cheng Sun¹, Xiuhong Pang⁴, Penghui Chen^{5

6

7}, Renjie Chai^{1

3}, Tao Yang^{5

6

7}, Hao Wu^{5

6

7}, Dong Liu¹

Affiliations

¹ Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital, School of Life Science, Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.
² Shanghai East Hospital, Department of Otorhinolaryngology Shanghai, Shanghai, China.
³ Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast University, Nanjing, China.
⁴ Department of Otorhinolaryngology-Head and Neck Surgery, Taizhou People's Hospital, Fifth Affiliated Hospital, Nantong University, Taizhou, China.
⁵ Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
⁶ Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China.
⁷ Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China.

Abstract

Apoptosis of cochlear hair cells is a key step towards age-related hearing loss. Although numerous genes have been implicated in the genetic causes of late-onset, progressive hearing loss, few show direct links to the proapoptotic process. By genome-wide linkage analysis and whole exome sequencing, we identified a heterozygous p.L183V variant in THOC1 as the probable cause of the late-onset, progressive, non-syndromic hearing loss in a large family with autosomal dominant inheritance. Thoc1, a member of the conserved multisubunit THO/TREX ribonucleoprotein complex, is highly expressed in mouse and zebrafish hair cells. The thoc1 knockout (thoc1 mutant) zebrafish generated by gRNA-Cas9 system lacks the C-startle response, indicative of the hearing dysfunction. Both Thoc1 mutant and knockdown zebrafish have greatly reduced hair cell numbers, while the latter can be rescued by embryonic microinjection of human wild-type THOC1 mRNA but to significantly lesser degree by the c.547C>G mutant mRNA. The Thoc1 deficiency resulted in marked apoptosis in zebrafish hair cells. Consistently, transcriptome sequencing of the mutants showed significantly increased gene expression in the p53-associated signaling pathway. Depletion of p53 or applying the p53 inhibitor Pifithrin-α significantly rescued the hair cell loss in the Thoc1 knockdown zebrafish. Our results suggested that THOC1 deficiency lead to late-onset, progressive hearing loss through p53-mediated hair cell apoptosis. This is to our knowledge the first human disease associated with THOC1 mutations and may shed light on the molecular mechanism underlying the age-related hearing loss.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Apoptosis / genetics
Benzothiazoles / pharmacology
CRISPR-Associated Protein 9 / genetics
DNA-Binding Proteins / deficiency
DNA-Binding Proteins / genetics*
Deafness / genetics*
Deafness / pathology
Disease Models, Animal
Exome Sequencing
Gene Expression Regulation / drug effects
Gene Knockout Techniques
Hair Cells, Auditory / metabolism
Hair Cells, Auditory / pathology
Hair Cells, Auditory, Inner / metabolism*
Hair Cells, Auditory, Inner / pathology
Humans
Mice
Mutation
RNA, Guide, CRISPR-Cas Systems
RNA-Binding Proteins / genetics*
Signal Transduction / drug effects
Toluene / analogs & derivatives
Toluene / pharmacology
Tumor Suppressor Protein p53 / antagonists & inhibitors
Tumor Suppressor Protein p53 / genetics*
Zebrafish / genetics

Substances

Benzothiazoles
DNA-Binding Proteins
RNA-Binding Proteins
THOC1 protein, human
Tumor Suppressor Protein p53
Toluene
pifithrin
CRISPR-Associated Protein 9

Supplementary concepts

Nonsyndromic Deafness

Grants and funding

This work was supported by National Natural Science Foundation of China (www.nsfc.gov.cn) (81641155 and 81870725 to LP.Z; 81970894 to TY; 81730028 to HW; 2018YFA0801004 and 81870359 to DL; 81700920 to XP and 81600802 to RZ), Shanghai Municipal Science and Technology Commission (http://stcsm.sh.gov.cn) (14DZ2260300 to HW) and Shanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant (http://edu.sh.gov.cn/) (20152519 to TY), Nantong science and technology plan frontier and key technology innovation fund (kjj.nantong.gov.cn) (MS22015048 to LP.Z); and the Natural Science Foundation from Jiangsu Province (http://kxjst.jiangsu.gov.cn/) (BK20180048 and 17KJA180008) to DL. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.