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细胞内膜网膜应激诱导GRP78的液体-液体相分离,并调节蛋白质聚合动态.
Jiaqi Li1,2, Xiangyu Zi1, Jiabao Fang1
1School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 1 Wenyuan Road, Nanjing, Jiangsu 210023, China.
ACS sensors
|May 23, 2025
概括
葡萄糖调节蛋白78 (GRP78) 在细胞应激下形成凝结物,招募与疾病相关的蛋白质,如SOD1 (A4V). 这种液-液相分离 (LLPS) 影响蛋白质聚合,为神经退行性疾病机制提供了洞察力.
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.
- 生物化学 生物化学
背景情况:
- 异常的蛋白质聚合是神经退行性疾病的核心.
- 葡萄糖调节蛋白78 (GRP78) 是 Endoplasmic 网膜 (ER) 中一个关键的伴侣,参与蛋白质折叠和 ER 应激.
- 最近的证据表明,GRP78参与液-液相分离 (LLPS),但其病理作用尚不清楚.
研究的目的:
- 为了研究 GRP78 液体-液体相分离 (LLPS) 在内质网膜 (ER) 应力下的功能影响.
- 探索GRP78凝结物与突变SOD1 (SOD1(A4V) 之间的相互作用,这是一种与肌缩侧面硬化症相关的蛋白质.
- 开发可用于可视化GRP78阶段过渡和相关微环境变化的工具.
主要方法:
- 新型光探针 (ER-Pro和Agg-Pro) 的设计和合成,用于GRP78标签和极性传感.
- 使用光终身成像显微镜 (FLIM) 和共聚焦显微镜.
- 分析SOD1 ((A4V) 进入GRP78凝结物的招募,并监测聚合动态.
主要成果:
- GRP78经历液体-液体相分离 (LLPS),以应对内质网膜 (ER) 应力.
- GRP78凝结物招募了与肌缩侧面硬化相关的突变SOD1 ((A4V),影响其聚合.
- SOD1 ((A4V) 聚合与局部极性转移相关,这表明GRP78 LLPS在蛋白质质量控制中的作用.
结论:
- GRP78液液相分离 (LLPS) 是一个动态过程,参与了细胞对ER压力的反应.
- GRP78凝结物可以调节与疾病相关的蛋白质的聚合,如SOD1 (A4V).
- 这些发现为ER稳态,神经退行性疾病病原体以及潜在的诊断/治疗策略提供了新的视角.
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