Moras D, Dock A C, Dumas P, Westhof E, Romby P, Ebel J P, Giegé R
Proc Natl Acad Sci U S A. 1986 Feb;83(4):932-6. doi: 10.1073/pnas.83.4.932.
The crystal structure of yeast tRNAAsp enables visualization of an anticodon-anticodon interaction at the molecular level. Except for differences in the base stacking and twist, the overall conformation of the anticodon loop is quite similar to that of yeast tRNAPhe. The anticodon nucleotide triplets, GUC, of two symmetrically related molecules form a minihelix of the RNA type 11. The modified base m1G37 stacks on both sides of the triplets and enforces the continuity with the anticodon stems. Anticodon association induces long-range conformational changes in the region of the dihydrouracil and thymine loops. Experimental evidence includes the variation in the distribution of temperature factors between yeast tRNAPhe and tRNAAsp, the difference in the self-splitting patterns of tRNAAsp in crystal and solution, and the differential accessibility of cytidines to dimethyl sulfate in free and duplex tRNAAsp. These observations are linked to the fragility and disruption of the G.C Watson-Crick base pair at the corner of the molecule formed by the dihydrouracil and thymine loops.
酵母天冬氨酸转运核糖核酸（tRNAAsp）的晶体结构能够在分子水平上呈现反密码子与反密码子之间的相互作用。除了碱基堆积和扭曲存在差异外，反密码子环的整体构象与酵母苯丙氨酸转运核糖核酸（tRNAPhe）的非常相似。两个对称相关分子的反密码子核苷酸三联体GUC形成了11型RNA的小螺旋。修饰碱基m1G37堆积在三联体两侧，并加强了与反密码子茎的连续性。反密码子缔合会在二氢尿嘧啶和胸腺嘧啶环区域诱导长程构象变化。实验证据包括酵母tRNAPhe和tRNAAsp之间温度因子分布的差异、tRNAAsp在晶体和溶液中自切割模式的不同，以及游离和双链tRNAAsp中胞嘧啶对硫酸二甲酯的不同可及性。这些观察结果与由二氢尿嘧啶和胸腺嘧啶环形成的分子角落处G.C沃森-克里克碱基对的脆弱性和破坏有关。
