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在真核生物中,NAC控制了共翻译的N终端甲酸切除

Martin Gamerdinger¹, Min Jia², Renate Schloemer¹

¹Department of Biology, Molecular Microbiology, University of Konstanz, 78457 Konstanz, Germany.

Science (New York, N.Y.)

|June 22, 2023

概括

新生的聚相关复合体 (NAC) 控制与核糖体结合的甲氨基酶 (METAP). 这确保了从细胞质蛋白中切除氨酸,同时保留了向细胞内网膜的蛋白质.

科学领域:

分子生物学
蛋白质生物化学
细胞平衡

背景情况:

N端 metionin 切除是一个由 metionin 氨基酶 (METAP) 催化的关键转换过程.
控制METAP与核糖体相互作用并确保分裂特异性的精确机制在很大程度上是未知的.
这一过程对于细胞平衡和适当的蛋白质生物生成至关重要.

研究的目的:

阐明甲氨基酶 (METAP) 与核糖体相互作用的机制.
了解蛋白质合成过程中如何实现甲胺切除特异性.
研究新生聚相关复合体 (NAC) 在调节METAP活性中的作用.

主要方法:

研究了METAP1与新生聚相关复合体 (NAC) 之间的相互作用.
使用生物化学分析来研究核糖体道出口的复杂形成.
检查了NAC对不同蛋白质类别的甲酸切除的影响.

主要成果:

发现新生聚相关复合体 (NAC) 控制了真核生物中METAP1的核糖体结合.
NAC通过灵活的尾巴招募METAP1,在核糖体道出口形成一个活跃的甲胺切除复合体.
这种相互作用可确保有效地从细胞质蛋白中切除甲,但不影响针对ER的蛋白质.

结论:

在核糖体中,NAC是甲氨基酶 (METAP) 活性的关键调节者.
为控制蛋白质生物发生因子进入翻译核糖体提出了一种新机制.
这一发现揭示了配译蛋白修饰的特异性.

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