野生类型和病原性形式的乌比奎林2对自-溶酶体通路的组件进行差异调节
Akiko Idera1, Lisa M Sharkey2, Yuki Kurauchi1
1Department of Chemico-Pharmacological Sciences, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan.
Journal of pharmacological sciences
|May 31, 2023
概括
乌比基林2 (UBQLN2) 突变会影响伴侣介导的自 (CMA) 和宏观自 (MA). 与ALS相关的UBQLN2突变加剧了这些退化途径缺陷,可能导致X相关的肌性侧面硬化症 (ALS) 中的神经退行.
科学领域:
- 细胞生物学 细胞生物学
- 神经科学是一个神经科学.
- 分子遗传学 分子遗传学
背景情况:
- 乌比奎林2 (UBQLN2) 中的错误突变是已知的X结合性肌性侧面硬化症 (ALS) 的已知原因.
- 据报道,与ALS相关的UBQLN2突变会损害蛋白质酶体介导的蛋白质降解.
- 这些突变对自-溶酶体通路的影响,包括宏自 (MA) 和伴侣介导自 (CMA),仍然在很大程度上没有表征.
研究的目的:
- 调查野生型和ALS相关突变UBQLN2如何影响CMA和MA.
- 确定UBQLN2在调节CMA活动中的作用.
- 阐明受损自对UBQLN2介导的ALS病原发生的贡献.
主要方法:
- 使用双CMA/mA光报道系统来评估自流量.
- 使用野生型和突变型UBQLN2.2的基因淘汰和稳定细胞系传染.
- 量化了LAMP2A (CMA相关) 与LAMP1 (溶酶体) 蛋白质的比例.
主要成果:
- 野生型UBQLN2的过度表达会损害CMA,而其敲击会增强CMA活性,表明UBQLN2对CMA有负面调节.
- 与ALS相关的突变UBQLN2与野生类型相比,加剧了CMA损伤.
- 野生型UBQLN2增加了LAMP2A/LAMP1比率,这表明了补偿机制,这种机制在突变UBQLN2.2的细胞中不存在.
- 发现突变UBQLN2,但不是野生类型,会损害MA.
结论:
- 两种CMA和MA都受到ALS相关突变UBQLN2.2的影响.
- 突变UBQLN2未能在CMA中引起补偿反应,进一步加剧了途径功能障碍.
- 这些联合自缺陷可能会导致UBQLN2相关的ALS中观察到的神经退行.
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