Regeneration of sensory hair cells in the mature cochlea is a major therapeutic challenge. Atoh1, a transcription factor important for hair cell development, can induce hair cell formation from surrounding supporting cells in postnatal murine cochleae. However, hair cells regenerated by Atoh1 are too few, are incompletely mature, and most importantly, exhibit age-dependent decline in the postnatal cochlea. It remains unclear which molecules and signaling pathways modulate Atoh1-mediated conversion of supporting cells to hair cells in the mature cochlea in vivo. Our preliminary results demonstrate that genetic manipulation of additional factors, in conjunction with Atoh1 activation, in supporting cells can convert them to hair cells in the mature cochlea in vivo. Remarkably, we also showed that one of the three factors by itself can convert supporting cells to hair cells in te mature cochlea in vivo. Moreover, we have established RNA profiles of newly regenerated hair cells that identify transcription factors and signaling molecules that are likely involved in regulation of Atoh1-mediated hair cell regeneration in the mature cochlea. These novel and exciting findings led us to test whether combined genetic manipulation of these molecules would increase the efficiency of conversion of supporting cells to hair cells in the mature cochlea in vivo and determine the molecular mechanisms of such conversion. Direct conversion of supporting cells to hair cells is a key initial step toward hair cell regeneration and functional restoration of hearing. Our approach has been highly fruitful in generating new hair cells in vivo?both previously, in the postnatal cochlea, and now in the mature cochlea. For example, we have achieved a conversion rate of supporting cells to hair cells as high as 20% in vivo, a rate comparable to those in other regenerative systems such as adult pancreas, heart, and CNS. Our proposed studies will reveal 1) novel mechanisms of hair cell regeneration in the mature mammalian cochlea and 2) novel therapeutic targets for future clinical restoration of hearing.

Public Health Relevance

Hearing impairment affects more than 10% of the human population, most hearing loss occurs after birth, when the cochlea is mature. To treat hearing loss, we propose to develop a series of mouse models that can regenerate sensory cells in the mature cochlea in vivo, by genetically manipulating a set of key genes in specific cells surrounding the sensory cells. Our results will provide novel targets and combinatory strategies for therapeutic treatment of human hearing loss.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
5R01DC015010-02
Application #
9248332
Study Section
Auditory System Study Section (AUD)
Program Officer
Freeman, Nancy
Project Start
2016-04-01
Project End
2021-03-31
Budget Start
2017-04-01
Budget End
2018-03-31
Support Year
2
Fiscal Year
2017
Total Cost
$460,087
Indirect Cost
$203,771
Name
St. Jude Children's Research Hospital
Department
Type
Independent Hospitals
DUNS #
067717892
City
Memphis
State
TN
Country
United States
Zip Code
38105
Teitz, Tal; Fang, Jie; Goktug, Asli N et al. (2018) CDK2 inhibitors as candidate therapeutics for cisplatin- and noise-induced hearing loss. J Exp Med 215:1187-1203
Hazlitt, Robert A; Min, Jaeki; Zuo, Jian (2018) Progress in the Development of Preventative Drugs for Cisplatin-Induced Hearing Loss. J Med Chem 61:5512-5524
Ban, David; Iconaru, Luigi I; Ramanathan, Arvind et al. (2017) A Small Molecule Causes a Population Shift in the Conformational Landscape of an Intrinsically Disordered Protein. J Am Chem Soc 139:13692-13700
Zheng, Fei; Zuo, Jian (2017) Cochlear hair cell regeneration after noise-induced hearing loss: Does regeneration follow development? Hear Res 349:182-196
Wood, Megan B; Zuo, Jian (2017) The Contribution of Immune Infiltrates to Ototoxicity and Cochlear Hair Cell Loss. Front Cell Neurosci 11:106
Lukashkina, Victoria A; Yamashita, Tetsuji; Zuo, Jian et al. (2017) Amplification mode differs along the length of the mouse cochlea as revealed by connexin 26 deletion from specific gap junctions. Sci Rep 7:5185
Walters, Bradley J; Coak, Emily; Dearman, Jennifer et al. (2017) In Vivo Interplay between p27Kip1, GATA3, ATOH1, and POU4F3 Converts Non-sensory Cells to Hair Cells in Adult Mice. Cell Rep 19:307-320
Teitz, Tal; Goktug, Asli N; Chen, Taosheng et al. (2016) Development of Cell-Based High-Throughput Chemical Screens for Protection Against Cisplatin-Induced Ototoxicity. Methods Mol Biol 1427:419-30
Zhang, Jian; Liu, Ziyi; Chang, Aoshuang et al. (2016) Abnormal mRNA splicing but normal auditory brainstem response (ABR) in mice with the prestin (SLC26A5) IVS2-2A>G mutation. Mutat Res 790:1-7