通过酵母苯丙氨酸转运RNA和天冬氨酸转运RNA对核糖核酸酶I的结构特异性进行探究。

Structural specificity of Rn nuclease I as probed on yeast tRNA(Phe) and tRNA(Asp).

作者信息

Przykorska A, el Adlouni C, Keith G, Szarkowski J W, Dirheimer G

机构信息

Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa.

出版信息

Nucleic Acids Res. 1992 Feb 25;20(4):659-63. doi: 10.1093/nar/20.4.659.

A single-strand-specific nuclease from rye germ (Rn nuclease I) was characterized as a tool for secondary and tertiary structure investigation of RNAs. To test the procedure, yeast tRNA(Phe) and tRNA(Asp) for which the tertiary structures are known, as well as the 3'-half of tRNA(Asp) were used as substrates. In tRNA(Phe) the nuclease introduced main primary cuts at positions U33 and A35 of the anticodon loop and G18 and G19 of the D loop. No primary cuts were observed within the double stranded stems. In tRNA(Asp) the main cuts occurred at positions U33, G34, U35, C36 of the anticodon loop and G18 and C20:1 positions in the D loop. No cuts were observed in the T loop in intact tRNA(Asp) but strong primary cleavages occurred at positions psi 55, C56, A57 within that loop in the absence of the tertiary interactions between T and D loops (use of 3'-half tRNA(Asp)). These results show that Rn nuclease I is specific for exposed single-stranded regions.

来自黑麦胚芽的单链特异性核酸酶（Rn核酸酶I）被鉴定为一种用于研究RNA二级和三级结构的工具。为了测试该程序，将已知三级结构的酵母tRNA（Phe）和tRNA（Asp）以及tRNA（Asp）的3'端半段用作底物。在tRNA（Phe）中，核酸酶在反密码子环的U33和A35位置以及D环的G18和G19位置引入主要的一级切割。在双链茎内未观察到一级切割。在tRNA（Asp）中，主要切割发生在反密码子环的U33、G34、U35、C36位置以及D环的G18和C20:1位置。在完整的tRNA（Asp）中，未在T环中观察到切割，但在T环和D环之间不存在三级相互作用的情况下（使用3'端半段tRNA（Asp）），该环内的ψ55、C56、A57位置发生了强烈的一级切割。这些结果表明，Rn核酸酶I对暴露的单链区域具有特异性。