Anticodon-anticodon interactions in solution: studies with yeast tRNAAsp

Bakers yeast tRNAAsp has been crystallized and its crystal structure is known at high resolution (Moras et al., 1980). This tRNA possesses a quasi-complementary anticodon (GUC) and crystal studies showed that the molecules are packed in the crystalline lattice in a way involving anticodon-anticodon interactions of the Watson-Crick type. Considering the existence of conformational differences between the structure of tRNAAsp and that of tRNAphe, where such an anticodon-anticodon interaction does not exist, it has been proposed that tRNAAsp structure represents a model of a tRNA interacting with mRNA (Westhof et al., 1983). On the other hand, it is well known that two tRNA species with complementary anticodons can form stable complexes in solution (Eisinger, 1971; Grosjean et al., 1978).