溶解体功能障碍和核酸过载在MNGIE的胺酸酸化酶缺乏中
Jixiang Du1,2,3, Fuchen Liu2, Xihan Liu4
1Department of Rheumatology and Immunology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, 250021, Shandong, China.
Journal of translational medicine
|May 13, 2024
概括
蒂米丁酸化酶 (TP) 缺乏导致MNGIE患者的溶解体功能障碍和核酸积累. 这项研究揭示了这种罕见的线粒体疾病背后的广泛的有机细胞破坏.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 由TYMP编码的遗传性胺酸酶 (TP) 缺乏导致线粒体神经胃肠道脑膜病变 (MNGIE),其特征是多个线粒体DNA (mtDNA) 异常.
- 对于线粒体质量控制和核酸代谢至关重要,TP缺乏对 lysosomal 功能的特定影响仍然在很大程度上未被探索.
研究的目的:
- 调查TP缺乏在溶酶体功能障碍中的作用及其对MNGIE病原发生的贡献.
- 在MNGIE患者和对照组中分析线粒体和 lysosomal 功能.
主要方法:
- 来自MNGIE患者,MELAS患者和健康对照的肌肉活检和皮肤纤维细胞的分析.
- 评估溶酶体酸度,酶活性,蛋白质降解和核酸积累,使用诸如溶酶体免疫沉 (Lyso-IP) 等技术.
- 在体外研究涉及TYMP淘汰/TP抑制和用核化物治疗 (dThd, dUrd).
主要成果:
- MNGIE患者的LAMP1表达减少,肌肉组织中的线粒体含量增加.
- 来自MNGIE患者的皮肤纤维细胞显示LAMP2表达减少,溶酶体酸度降低,酶活性受损,蛋白质降解减少.
- TP缺乏导致核酸,线粒体蛋白质的溶解体积累,以及囊泡蛋白和V-ATPase酶的水平降低.
- 在细胞模型中,高核酸度诱导了溶酶体功能障碍和线粒体失衡.
结论:
- TP缺乏直接导致溶解体功能障碍和核酸积.
- Lysosomal 损伤是 MNGIE 发病的一个重要因素,有助于广泛的器官破坏.
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