一个与核糖体关联的伴侣介导GTP驱动的新生eEF1AA的矢量折叠
Ibrahim M Sabbarini1, Dvir Reif1, Kibum Park2
1Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA.
Nature communications
|February 3, 2025
概括
研究人员发现了Ypl225w,这是一种共同翻译的陪伴者,可以稳定新生的真核细胞翻译延长因子1A (eEF1A) G域. 这种伴侣确保了正确的eEF1A折叠,并为蛋白质合成期间的GTP结合做了准备.
科学领域:
- 分子生物学分子生物学
- 蛋白质折叠 蛋白质的折叠
- 生物化学 生物化学
背景情况:
- 细胞翻译延长因子1A (eEF1A) 对于蛋白质合成至关重要.
- 虽然已经了解过翻译后折叠,但对eEF1A的共同翻译折叠机制仍然未知.
- eEF1A的N端GTP结合域容易发生错折.
研究的目的:
- 确定涉及eEF1A折叠的共同翻译机制.
- 描述合成过程中与eEF1A相互作用的新型伴侣蛋白的功能.
- 阐明陪伴者在确保eEF1A生物发生和功能中的作用.
主要方法:
- 阿尔法Pulldown测试以识别相互作用的蛋白质.
- 计算模拟用于预测蛋白质折叠倾向.
- 微镜分析缺乏已识别的伴侣的酵母细胞.
- 蛋白质组学和生物化学复合实验.
- 对伴侣-新生链和伴侣-核糖体相互作用的分析.
主要成果:
- 确定Ypl225w (Chp1) 是一种保存的酵母蛋白,可以稳定eEF1A G域.
- Ypl225w 作为一个协同翻译的伴侣,与新生的 eEF1A G 域和与核糖体结合的 NAC 相互作用.
- Ypl225w促进了GTP与新生eEF1A链的结合,将折叠与核酸结合相结合.
- 伴奏作用是独立于ATP的,并促进矢量折叠.
结论:
- Ypl225w是一种新型的共同翻译伴侣,对eEF1A生物发生是必不可少的.
- 这一发现揭示了新生GTPases的矢量折叠的新机制.
- 这些发现突出显示了在翻译过程中伴侣活动与G蛋白核酸结合的整合.
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