Zebrafish myo7aa affects congenital hearing by regulating Rho-GTPase signaling

Binling Xie; Jiaxin Liang; Jifan Jiang; Ting Zeng; Ling Liu; Dinghua Xie; Ganghua Zhu; Lei Xiong; Kanjia Zhang; Dong Liu; Jie Gong; Xiangding Chen; Ruosha Lai; Huaping Xie

doi:10.3389/fnmol.2024.1405109

Zebrafish myo7aa affects congenital hearing by regulating Rho-GTPase signaling

Front Mol Neurosci. 2024 Jul 15:17:1405109. doi: 10.3389/fnmol.2024.1405109. eCollection 2024.

Authors

Binling Xie^#^{1

2

3}, Jiaxin Liang^#^{1

2

3}, Jifan Jiang^#^{1

2}, Ting Zeng^{1

2}, Ling Liu^{1

2}, Dinghua Xie⁴, Ganghua Zhu⁴, Lei Xiong^{1

2

3}, Kanjia Zhang⁴, Dong Liu⁵, Jie Gong⁵, Xiangding Chen³, Ruosha Lai⁴, Huaping Xie¹

Affiliations

¹ Laboratory of Animal Nutrition and Human Health, Hunan International Joint Laboratory of Animal Intestinal Ecology and Health, College of Life Science, Hunan Normal University, Changsha, Hunan, China.
² State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, Hunan, China.
³ Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Hunan Normal University, Changsha, China.
⁴ Department of Otorhinolaryngology-Head & Neck Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China.
⁵ Nantong Laboratory of Development and Diseases, Key Laboratory of Neuroregeneration of Jiangsu and MOE, School of Life Sciences, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China.

^# Contributed equally.

Abstract

Introduction: myo7aa, the homolog of the human Usher 1B syndrome pathogenic gene, myo7A, plays an important role in stereociliary development and maintenance, therefore, is critical for hearing and balance. However, the molecular mechanisms that myo7aa regulate hearing and balance still need to be studied.

Methods: In this study, we generated two independent zebrafish myo7aa knockout lines using CRISPR/Cas9 technology. To investigate the effects of myo7aa on hearing, YO-PRO-1 staining and startle response assay were used. To gain insight into the specific molecular mechanisms by which myo7aa affects hearing, transcriptome sequencing and bioinformatics analysis were employed.

Results: Our study showed that hair cells of myo7aa-/- zebrafish can not take up YO-PRO-1 fluorescent dye and are insensitive to acoustic stimulation in myo7aa-/- zebrafish compared to wild type. Genes related to the Rho GTPase signaling pathway, such as arhgap33, dab2ip, and arghef40, are significantly down-regulated in myo7aa-/- zebrafish embryos at 3 dpf. GTP and ATP compensation can partially rescue the hair cell defects in myo7aa knockout zebrafish.

Discussion: Our findings suggest that zebrafish myo7aa affects congenital hearing by regulating Rho GTPase signaling, and loss of myo7aa leads to abnormal Rho GTPase signaling and impairs hair cell function. myo7aa, myo7A, arhgap33, dab2ip, arghef40 and myo7aa-/- fonts in the abstract are italicized. -/- is a superscript format.

Keywords: CRISPR/Cas9; Rho GTPase signaling; hearing; myo7aa; zebrafish.

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. This research was funded by National Natural Science Foundation of China (82170308), Xiaoxiang Scholar Distinguished Professor Startup Funding for H-pX (053112–3826), Science Foundation of Hunan Provincial Health Commission (202000666); Natural Science Foundation of Hunan Province (2023JJ30753) and Natural Science Foundation of Changsha (kq2208326).