硫氨基酸通过调节tRNA硫化的调节来调节转化能力和代谢平衡
Sunil Laxman1, Benjamin M Sutter, Xi Wu
1Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038, USA.
Cell
|July 23, 2013
概括
细胞中的硫氨基酸水平控制tRNA化,这是对蛋白质翻译和生长至关重要的修改. 这一发现揭示了代谢平衡和细胞适应营养变化的关键机制.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞的新陈代谢
背景情况:
- 蛋白质翻译是一个耗费大量能量的过程,需要根据营养素的可用性进行严格的调节.
- 转移RNA (tRNA) 的修饰,如摇摆尿素 (U34) 的硫化,对于细胞功能至关重要,特别是在压力下.
- 特定的tRNAs (氨酸,谷氨酸,谷氨酸) 参与翻译富含生长相关蛋白质的编码子.
研究的目的:
- 为了研究细胞内硫氨基酸的可用性和tRNA硫化状态之间的直接联系.
- 阐明tRNA硫化在调节细胞转化能力和代谢平衡中的作用.
- 了解细胞在硫饥饿期间使用的适应机制.
主要方法:
- 细胞内 metionin 和cysteine 水平的分析.
- 对特定tRNA (lysine,glutamine,glutamate) 的tRNA硫化状态的评估.
- 测量细胞转化能力和基因表达.
- 评估代谢途径,包括氨基酸生物合成.
主要成果:
- 细胞内 metionin 和 cysteine 的可用性直接控制了 U34 核酸在 lysine, glutamine 和 glutamate tRNA 上的 thiolation 状态.
- 在硫饥饿期间,tRNA硫化被下调,减少了硫的消耗和生长.
- 缺少tRNA硫化导致 metionin,cysteine 和 lysine 的生物合成增加.
- 对于编码参与生长和翻译的蛋白质的基因的高效翻译,tRNA硫化是必不可少的.
结论:
- tRNA硫化作用作为硫氨基酸可用性的关键传感器和调节器,调节转化能力.
- 这种保存的tRNA修饰在控制细胞生长和维持代谢平衡中起着重要作用.
- 细胞利用tRNA硫化来调整它们的转化机制以适应波动的营养条件,特别是硫的可用性.
相关概念视频
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01:31Translation
Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
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Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
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01:31Translation
Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life