THE CONTACTS OF YEAST TRANSFER RNASER WITH SERYL-TRANSFER RNA-SYNTHETASE STUDIED BY FOOTPRINTING EXPERIMENTS
THE CONTACTS OF YEAST TRANSFER RNASER WITH SERYL-TRANSFER RNA-SYNTHETASE STUDIED BY FOOTPRINTING EXPERIMENTS
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DOI：
10.1111/j.1432-1033.1990.tb15401.x
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发表时间：
1990-03-10
期刊：
影响因子：
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通讯作者：
MORAS, D
中科院分区：
文献类型：
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作者：
DOCKBREGEON, AC;GARCIA, A;MORAS, D
酵母tRNASer是II类tRNA的一员，其特征是存在延伸的可变环。这种额外的结构特征引发了关于这些 II 类 tRNA 的同源合成酶识别以及额外臂参与识别过程的可能性的问题。对与其同源合成酶、酵母丝氨酰-tRNA合成酶（α2二聚体）复合的酵母tRNAser进行了足迹研究。实验中使用化学（乙亚硝基脲）和酶（核酸酶 S1 和 V1）探针。建立了 tRNA 和合成酶之间接触点的图谱，并根据酵母 tRNASer 的三维模型对结果进行了分析。与合成酶邻近的区域聚集在 tRNA 的一个面上。额外的臂受到严格保护，免受化学修饰，是接触区域的重要组成部分。相反，当复合物形成时，反密码子三联体和大部分反密码子臂仍然可以被探针接近。这些结果是在氨酰化反应中 tRNA 识别的背景下讨论的。
Yeast tRNASer is a member of the class II tRNAs, whose characteristic is the presence of an extended variable loop. This additional structural feature raises questions about the recognition of these class II tRNAs by their cognate synthetase and the possibility of the involvement of the extra arm in the recognition process. A footprinting study of yeast tRNAser complexed with its cognate synthetase, yeast seryl-tRNA synthetase (an .alpha.2 dimer), was undertaken. Chemical (ethynitrosourea) and enzymatic (nucleases S1 and V1) probes were used in the experiments. A map of the contact points between the tRNA and the synthetase was established and results were analyzed with respect to a three-dimensional model of yeast tRNASer. Regions in close vicinity with the synthetase are clustered on one face of tRNA. The extra arm, which is strongly protected from chemical modifications, appears as an essential part of the contact area. The anticodon triplet and a large part of the anticodon arm are, in contrast, still accessible to the probes when the complex is formed. These results are discussed in the context of the recognition of tRNAs in the aminoacylation reaction.