在ERAD功能障碍时,ER-to-lysosome相关的降解起到安全机制的作用
Elisa Fasana1, Ilaria Fregno1, Carmela Galli1
1Faculty of Biomedical Sciences, Institute for Research in Biomedicine, Università della Svizzera italiana (USI), 6500, Bellinzona, Switzerland.
EMBO reports
|May 21, 2024
概括
当阻断内质网膜相关降解 (ERAD) 时,细胞会激活ER-lysosome相关降解 (ERLAD) 途径. 这种由FAM134B驱动的过程清除了错误折叠的蛋白质,确保了细胞蛋白质稳定.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白质降解 蛋白质降解
背景情况:
- 细胞内膜网膜 (ER) 对于蛋白质合成和折叠至关重要.
- 错误折叠的蛋白质通常通过涉及蛋白质酶的ER相关降解 (ERAD) 降解.
- 大量的错误折叠蛋白质或ERAD功能障碍可能导致其他降解路径.
研究的目的:
- 调查ERAD功能障碍的补偿机制.
- 探索ER-to-lysosome相关降解 (ERLAD) 在清除ERAD客户端中的作用.
- 为了阐明FAM134B在ERAD妥协条件中的参与.
主要方法:
- 药理学和基因抑制ERAD组件 (EDEM1,OS9) 的作用.
- 对正规ERAD客户端 (NHK,BACE457Δ) 局部化和退化的分析.
- 评估FAM134B受体和LC3脂化机制的参与.
主要成果:
- 抑制ERAD组件触发了ERAD客户端的输送到内分泌体.
- 这种传递取决于ER-phagy受体FAM134B和LC3的脂化.
- ERAD功能障碍激活了FAM134B介导的ERLAD蛋白质清除途径.
结论:
- 由于ERAD功能障碍,可以激活补偿ERLAD通路.
- 当ERAD受损时,FAM134B在ERAD客户的溶酶体清除中发挥着关键作用.
- 这些发现突出了在ER压力下维持蛋白质静止的关键机制.
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