在核糖体中,Chp1是一个专门的伴侣,它保证了eEF1A生物发生
Melania Minoia1, Jany Quintana-Cordero1, Katharina Jetzinger1,2
1Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden.
Nature communications
|February 15, 2024
概括
一个新发现的伴侣,Chp1,在合成过程中对于真核细胞翻译延长因子1A (eEF1A) 的正确折叠至关重要. 没有Chp1,细胞经历蛋白质稳定性崩,但Chp1也可以防止与疾病相关的eEF1A变异.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 蛋白质折叠 蛋白质的折叠
背景情况:
- 一般的陪伴者在核糖体的共同翻译折叠过程中协助各种新生的蛋白质.
- 基本蛋白质的生物发生需要专门的机制来确保适当的折叠和功能.
研究的目的:
- 识别和描述参与特定真核细胞蛋白的共翻译折叠的新型伴侣.
- 阐明Chp1在真核细胞翻译延长因子1A (eEF1A) 的生物发生中的作用.
主要方法:
- 核糖体剖析和共免疫沉以确定核糖体相关的因素.
- 基因操纵 (例如,基因删除) 来评估Chp1.1的体内功能.
- 对蛋白质聚合,蛋白质分解和应激反应标记物的分析.
主要成果:
- Chp1是一个专门的核糖体关联的伴侣,专门协助eEF1A生物发生.
- 在eEF1A合成过程中,Chp1通过新生的多相关复合体 (NAC) 被招募到核糖体中.
- 丢失Chp1导致eEF1A蛋白质解,蛋白质聚合,HSF1激活,并影响细胞健康.
- Chp1表达能防止与性失动性脑病变相关的致病性eEF1A2变异.
结论:
- eEF1A是一种难以折叠的蛋白质,需要由核糖体中的Chp1启动的专用生物发生路径.
- 通过防止错误折叠的eEF1A的积累,Chp1对于维持蛋白质稳定至关重要.
- 向Chp1可能为与eEF1A功能障碍相关的疾病提供治疗策略.
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