Ren Mengmeng, Chen Xiang, Dai Liyan, Tu Jiayi, Hu Hualei, Sun Xiaohan, Luo Jiong, Li Pei, Fu Yiyang, Zhu Yuejie, Sun Weiqiang, Tang Zhaohui, Liu Mugen, Ren Xiang, Lu Qunwei
Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Center for Human Genome Research, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China.
Section of Hematology and Oncology, Department of Medicine, The University of Chicago, Chicago, IL 60637, USA.
Biomedicines. 2024 Dec 26;13(1):20. doi: 10.3390/biomedicines13010020.
: Alternative splicing is essential for the physiological and pathological development of the inner ear. Disruptions in this process can result in both syndromic and non-syndromic forms of hearing loss. DHX38, a DEAH box RNA helicase, is integral to pre-mRNA splicing regulation and plays critical roles in development, cell differentiation, and stem cell maintenance. However, its specific role in inner ear development remains undefined. Here, we utilized a knockout zebrafish model to monitor the ear morphology and elucidate a crucial role for DHX38 in the development of the zebrafish inner ear. : Bright-field morphological analysis and in situ hybridization were performed to observe ear morphology changes. Immunofluorescence and semi-quantitative RT-PCR were employed to test apoptotic cells and abnormal splicing. : The mutant zebrafish showed significant inner ear impairments, including decrescent otocysts, absent semicircular canal protrusion, and smaller otoliths. These structural abnormalities were accompanied by substantial DNA damage and p53-dependent apoptosis within the inner ear cells. Alternative splicing analysis showed that genes related to DNA damage repair and inner ear morphogenesis are abnormal in knockout mutants. In summary, we suggest that promotes cell survival during the inner ear development of zebrafish by ensuring the correct splicing of genes related to DNA damage repair.
可变剪接对于内耳的生理和病理发育至关重要。这一过程的破坏可导致综合征性和非综合征性听力损失。DHX38是一种DEAH盒RNA解旋酶，是前体mRNA剪接调控所必需的，并且在发育、细胞分化和干细胞维持中起关键作用。然而，其在内耳发育中的具体作用仍不明确。在此，我们利用基因敲除斑马鱼模型来监测耳部形态，并阐明DHX38在斑马鱼内耳发育中的关键作用。进行明场形态分析和原位杂交以观察耳部形态变化。采用免疫荧光和半定量RT-PCR检测凋亡细胞和异常剪接。基因敲除突变斑马鱼表现出明显的内耳损伤，包括耳囊变小、半规管突出缺失和耳石变小。这些结构异常伴随着内耳细胞内大量的DNA损伤和p53依赖性凋亡。可变剪接分析表明，在基因敲除突变体中，与DNA损伤修复和内耳形态发生相关的基因异常。总之，我们认为DHX38通过确保与DNA损伤修复相关基因的正确剪接，在斑马鱼内耳发育过程中促进细胞存活。
