在大肠杆菌中对蛋白质表达的影响与mRNA水平相关
Grégory Boël1,2,3, Reka Letso1,2, Helen Neely1,2
1Department of Biological Sciences, 702A Fairchild Center, MC2434, Columbia University, New York, NY 10027, USA.
Nature
|January 14, 2016
概括
基因代码退化通过调节mRNA降解和蛋白质延长动力学来影响蛋白质表达. 不仅使用频率,还影响大肠杆菌的基因表达水平.
科学领域:
- 分子生物学
- 遗传学
- 生物化学
背景情况:
- 遗传密码的退化允许多个DNA序列编码相同的蛋白质,从而影响基因表达.
- 同义代码子影响蛋白质和mRNA水平的确切机制尚不完全理解.
研究的目的:
- 研究影响蛋白质表达水平的序列特征,特别是代码子含量.
- 开发一种对基因表达的子影响的指标,并将其与mRNA折叠参数进行比较.
主要方法:
- 用菌体T7聚合酶进行大肠杆菌mRNA合成的6348项实验的分析.
- 应用后勤回归来得出一种新的子影响度量.
- 与基因组基因组使用和mRNA折叠参数对代码的影响的比较.
主要成果:
- 一个新的密码体影响指标显示与密码体使用的相关性很弱,但与蛋白质和mRNA度和寿命的相关性很强.
- 代码子含量是蛋白质表达的更强的决定因素,而不是mRNA折叠,除了最初的16个代码子.
- 重新设计的基因表现出类似的转录,但在体外翻译得到增强,原生无效序列显示出体内mRNA水平降低.
结论:
- 通过影响蛋白质延长和mRNA降解之间的平衡,Codon含量显著调节蛋白质表达.
- 这种运动竞争是大肠杆菌生理学和转化调节的关键方面.
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