类蛋白质. 类蛋白质. CRL2有助于消除由于UGA/Sec解码失败而产生的截断的烯蛋白
Hsiu-Chuan Lin1, Szu-Chi Ho2, Yi-Yun Chen3
1Institute of Molecular Biology, Academia Sinica, Taiwan. Genome and Systems Biology Degree Program, National Taiwan University, Taiwan.
Science (New York, N.Y.)
|July 4, 2015
概括
这项研究揭示了一种蛋白质质量控制系统,当单半氨酸 (Sec) 翻译失败时,它会降解截断的蛋白质. 这种机制通过消除由水平波动引起的缺陷蛋白质来确保蛋白质组的忠实性.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 单类固醇 (Sec) 是一种由UGA编码子编码的氨基酸,它通常标志着翻译终止.
- 对于Sec的纳入与终止,UGA的双重解码对蛋白质组忠实性构成了挑战.
- 需要细胞机制来管理由这种编码子二元性产生的潜在错误.
研究的目的:
- 调查蛋白质质量控制机制,以确保蛋白质组忠实性在氨基氨酸的合并的背景下.
- 为了确定细胞如何处理由UGA-codon重新分配失败导致的截断蛋白质.
- 阐明翻译,蛋白质降解和的可用性之间的相互作用.
主要方法:
- 使用了一种CRL2泛基因酶介导的蛋白质降解试验.
- 研究了一种特定的N端序列作为降解剂的作用.
- 分析了Sec结合对蛋白质稳定性和降解途径的影响.
主要成果:
- 鉴定了一种CRL2泛基因酶系统,该系统专门针对由Sec翻译错误引起的截断蛋白.
- 一个N端到Sec的序列作为CRL2的识别降解体,促进不完整蛋白质的降解.
- 在UGA编码子上成功的Sec合并破坏了降解子,从而保护了全长蛋白质免受降解.
结论:
- 定向翻译终止与蛋白质分解辅助的蛋白质质量控制之间存在直接联系.
- 这个系统提供了一个细胞战略,以保持蛋白质组完整性,尽管水平变化.
- 这些发现突出了一个复杂的机制来管理扩展遗传密码的固有风险.
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