Nameki N, Asahara H, Shimizu M, Okada N, Himeno H
Institute of Space and Astronautical Science, Kanagawa, Japan.
Nucleic Acids Res. 1995 Feb 11;23(3):389-94. doi: 10.1093/nar/23.3.389.
Recognition of tRNA(His) by Saccharomyces cerevisiae histidyl-tRNA synthetase was studied using in vitro transcripts. Histidine tRNA is unique in possessing an extra nucleotide, G-1, at the 5' end. Mutation studies indicate that this irregular secondary structure at the end of the acceptor stem is important for aminoacylation with histidine, while the requirement of either base of this extra base pair is smaller than that in Escherichia coli. The anticodon was also found to be required for histidylation. The regions involved in histidylation are essentially the same as those in E.coli, whereas the proportion of the contributions of the two portions distant from each other, the anticodon and the end of the acceptor stem, makes a substantial difference between the two systems.
利用体外转录本研究了酿酒酵母组氨酰 - tRNA合成酶对tRNA(His)的识别。组氨酸tRNA的独特之处在于其5'端拥有一个额外的核苷酸G - 1。突变研究表明，受体茎末端这种不规则的二级结构对于组氨酸的氨酰化很重要，而这个额外碱基对中任一碱基的需求比大肠杆菌中的要小。还发现反密码子对于组氨酰化也是必需的。参与组氨酰化的区域与大肠杆菌中的基本相同，然而，在这两个系统中，相互远离的两个部分（反密码子和受体茎末端）的贡献比例存在显著差异。
