Selective charging of tRNA isoacceptors explains patterns of codon usage
Selective charging of tRNA isoacceptors explains patterns of codon usage
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DOI：
10.1126/science.1083811
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发表时间：
2003-06-13
期刊：
影响因子：
56.9
通讯作者：
Ehrenberg, M
中科院分区：
文献类型：
--
作者：
Elf, J;Nilsson, D;Ehrenberg, M
我们模拟了当这种氨基酸变得限制生长时，携带相同氨基酸（同工受体）的不同转移 RNA (tRNA) 的电荷水平如何反应。某些同工受体（例如 tRNA(2)(Leu)）的带电水平将接近零，而其他同工受体（例如 tRNA(4)(Leu)）的带电水平则保持较高水平，具体取决于同工受体的浓度及其密码子在蛋白质合成中出现的频率。该理论解释了核糖体介导的转录衰减中使用的相同氨基酸的（同义）密码子、反式翻译转移信使RNA中同义密码子的选择，以及氨基酸生物合成酶的信使RNA中稀有密码子的过度表达。
We modeled how the charged levels of different transfer RNAs (tRNAs) that carry the same amino acid ( isoacceptors) respond when this amino acid becomes growth-limiting. The charged levels will approach zero for some isoacceptors (such as tRNA(2)(Leu)) and remain high for others (such as tRNA(4)(Leu)), as determined by the concentrations of isoacceptors and how often their codons occur in protein synthesis. The theory accounts for ( synonymous) codons for the same amino acid that are used in ribosome-mediated transcriptional attenuation, the choices of synonymous codons in trans-translating transfer-messenger RNA, and the overrepresentation of rare codons in messenger RNAs for amino acid biosynthetic enzymes.