Uniform binding of aminoacyl-tRNAs to elongation factor Tu by thermodynamic compensation
Uniform binding of aminoacyl-tRNAs to elongation factor Tu by thermodynamic compensation
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DOI：
10.1126/science.1064242
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发表时间：
2001-10-05
期刊：
影响因子：
56.9
通讯作者：
Uhlenbeck, OC
中科院分区：
文献类型：
--
作者：
LaRiviere, FJ;Wolfson, AD;Uhlenbeck, OC
在蛋白质合成过程中，延伸因子Tu(EF-Tu)结合所有的延伸子氨基酰基转移RNA(AA-tRNAs)，将其运送到核糖体。在这里，我们证明了EF-Tu在更广泛的范围内与错酰化的tRNA结合，而不是与相应的正确酰化的tRNAs结合，这表明该蛋白对氨基酸侧链和tRNA小体都表现出相当大的特异性。当tRNA正确酰化时，氨基酸和tRNA小体对总结合亲和力的热力学贡献是相互独立的，并相互补偿。由于某些错酰化的tRNA与EF-Tu的结合明显强于或弱于同源的AA-tRNA，EF-Tu可能有助于翻译的准确性。
Elongation factor Tu (EF-Tu) binds all elongator aminoacyl-transfer RNAs (aa-tRNAs) for delivery to the ribosome during protein synthesis. Here, we show that EF-Tu binds misacylated tRNAs over a much wider range of affinities than it binds the corresponding correctly acylated tRNAs, suggesting that the protein exhibits considerable specificity for both the amino acid side chain and the tRNA body. The thermodynamic contributions of the amino acid and the tRNA body to the overall binding affinity are independent of each other and compensate for one another when the tRNAs are correctly acylated. Because certain misacylated tRNAs bind EF-Tu significantly more strongly or weakly than cognate aa-tRNAs, EF-Tu may contribute to translational accuracy.