Structural Basis of Transfer Ribonucleic Acid Function

本研究的目标是确定序列， 转移核糖核酸结构元件 这是蛋白质识别所必需的。 特别 兴趣是对E.氨基酸的大肠杆菌tRNA 缬氨酸（tRNAVa 1）通过氨酰-tRNA合成酶和tRNA 修饰酶，tRNA（尿嘧啶-5-）甲基转移酶。详细 了解这些相互作用将澄清问题 关于蛋白质合成的保真度， 的tRNA修饰，以及修饰的核苷在 tRNA功能 tRNAVa 1的元件对于其功能至关重要。 将确定缬氨酰-tRNA合成酶（VRS）的识别 通过检查tRNAVa 1变体的反应动力学。 合成酶识别的最低要求将是 用含有基本识别基因的tRNA片段进行探索， tRNAVa 1的启动元件。 这些突变体的结构 将通过tRNAVa 1标记的19 F NMR光谱探测tRNA。 以氟为主导。 氟化tRNAVa 1非常适合于 这些研究，因为它仍然充分发挥作用，并包含 高灵敏度的19 F探针分布在所有的 螺旋茎和环的tRNA分子， 可以监测当地的结构 变化

The goals of this research are to define the sequence and structural elements of transfer ribonucleic acid (tRNA) required for its recognition by proteins. Of particular interest is the recognition of E. coli tRNA for amino acid valine (tRNAVa1) by aminoacyl-tRNA synthetases and by the tRNA modifying enzyme, tRNA (uracil-5-)methyltransferase. Detailed understanding of these interactions will clarify questions concerning the fidelity of protein synthesis, the mechanisms of tRNA modification, and the role of modified nucleosides in tRNA function. The elements of tRNAVa1 essential for its recognition by valyl-tRNA synthetase (VRS) will be determined by examining the kinetics of reaction of tRNAVa1 variants. Minimal requirements for synthetase recognition will be explored with tRNA fragments containing the essential recog- nition elements of tRNAVa1. The structure of these mutant tRNAs will be probed by 19F NMR spectroscopy of tRNAVa1 labe- led with fluorine. Fluorinated tRNAVa1 is ideally suited for such studies because it remains fully functional and contains highly sensitive 19F probes distributed throughout all the helical stems and the loops of the tRNA molecule where they can serve to monitor local structural changes.