自细胞标记物LC3通过几个不同的途径在细胞外释放
Koki Saito1,2, Masashi Arakawa1, Koki Maeda1,2
1Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Japan.
FEBS open bio
|November 10, 2025
概括
研究人员开发了一种敏感的HiBiT标签系统,以研究LC3 (微管相关蛋白1A/1B光链3) 的自介导分泌. 这项研究揭示LC3释放取决于自细胞形成,但也独立发生,表明多个分泌途径.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 自对于通过细胞质成分的分泌来维持细胞内平衡至关重要.
- 控制自介导分泌的精确机制,特别是像LC3这样的特定蛋白质的释放,仍然不完全理解.
研究的目的:
- 开发和使用一种超敏感的检测系统来分析触发LC3 (微管相关蛋白1A/1B-光链3) 分泌的条件.
- 调查自细胞形成和其他机制在LC3释放到细胞外空间中的作用.
主要方法:
- 开发一种使用HiBiT标签/纳米BiT技术的超敏感检测系统,用于量化细胞外HiBiT融合LC3.
- 在野生型,ATG5/FIP200淘汰细胞和具有特定LC3突变的细胞 (C端截断ΔG,K51A/L53A突变) 中分析HiBiT-LC3释放.
- 用巴菲洛米辛A1和洗剂进行治疗,分别调节自菌体-溶酶体融合和膜结合.
主要成果:
- 细胞外HiBiT-LC3被检测到在培养超级生物中,需要洗剂释放,表明与脂质膜分离.
- 巴菲洛米辛A1治疗增加了细胞外HiBiT-LC3,并且这种增加在ATG5或FIP200淘汰细胞中减少,这表明对自细胞形成的依赖.
- 在淘汰细胞中部分观察到LC3释放,并被LC3突变减少但没有被消除,表明存在自依赖的和独立的释放通路.
结论:
- 开发的HiBiT标签/纳米BiT系统为研究自介导分泌提供了一个敏感的工具.
- LC3分泌主要依赖于自细胞形成,但也可以通过自细胞独立的机制发生.
- 多种途径有助于细胞外释放LC3,凸显了这种细胞过程的复杂性.
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