Crystal structure of group II intron domain 1 reveals a template for RNA assembly.

摘要: Although the importance of large noncoding RNAs is increasingly appreciated, our understanding their structures and architectural dynamics remains limited. In particular, we know little about RNA folding intermediates how they facilitate productive assembly tertiary structures. Here, report crystal structure an obligate intermediate that required during earliest stages group II intron folding. Composed domain 1 from Oceanobacillus iheyensis (266 nucleotides), this retains native-like features but adopts a compact conformation in which active site cleft closed. Transition between closed open (native) achieved through discrete rotations hinge motifs two regions molecule. The state then stabilized by sequential docking downstream domains, suggesting 'first come, first folded' strategy may represent generalizable pathway for ribonucleoprotein