Mutants of Escherichia coli initiator tRNA that suppress amber codons in Saccharomyces cerevisiae and are aminoacylated with tyrosine by yeast extracts.
Mutants of Escherichia coli initiator tRNA that suppress amber codons in Saccharomyces cerevisiae and are aminoacylated with tyrosine by yeast extracts.
复制标题
大肠杆菌起始子 tRNA 突变体，可抑制酿酒酵母中的琥珀密码子，并被酵母提取物用酪氨酸氨酰化。
DOI：
10.1073/pnas.88.24.11378
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发表时间：
1991
影响因子：
11.1
通讯作者：
RajBhandary,UL
中科院分区：
文献类型：
--
作者：
Lee,CP;RajBhandary,UL
我们最近描述了大肠杆菌起始tRNA的突变体，其抑制大肠杆菌中的琥珀终止密码子（UAG）。杆菌这些突变体在反密码子序列（CAU-CUA）上发生了变化，使它们能够读取琥珀密码子，在受体茎上发生了变化，使它们能够与核糖体氨酰基（A）位点结合。我们在这里表明，这些突变体的一个子集抑制琥珀密码子在酿酒酵母，它们是氨基酰化与酪氨酸的酵母提取物。对作为酵母酪氨酰-tRNA合成酶底物的许多突变体的分析已经导致鉴定了C1.G72碱基对和C1.G72碱基A73，其在所有真核细胞质和古细菌酪氨酸tRNA中保守，对于识别是重要的。我们的结果表明，除了先前鉴定的反密码子核苷酸[Bare，L.A. & Uhlenbeck，O.C.（1986）Biochemistry 25，5825-5830]，其在酵母酪氨酰-tRNA合成酶识别中是重要的，可以包含酵母酪氨酸tRNA中的关键同一性决定簇。
We recently described mutants of Escherichia coli initiator tRNA that suppress amber termination codons (UAG) in E. coli. These mutants have changes in the anticodon sequence (CAU----CUA) that allow them to read the amber codon and changes in the acceptor stem that allow them to bind to the ribosomal aminoacyl (A) site. We show here that a subset of these mutants suppress amber codons in Saccharomyces cerevisiae and that they are aminoacylated with tyrosine by yeast extracts. Analysis of a number of mutants as substrates for yeast tyrosyl-tRNA synthetase has led to identification of the C1.G72 base pair and the discriminator base A73, conserved in all eukaryotic cytoplasmic and archaebacterial tyrosine tRNAs, as being important for recognition. Our results suggest that the C1.G72 base pair and the discriminator base, in addition to the anticodon nucleotides previously identified [Bare, L.A. & Uhlenbeck, O.C. (1986) Biochemistry 25, 5825-5830] as important in yeast tyrosyl-tRNA synthetase recognition, may comprise the critical identity determinants in yeast tyrosine tRNA.