Tertiary Motifs in RNA Structure and Folding.

Specific tertiary structural motifs determine the complete architecture of RNA molecules (see picture for examples). Within the last few years a number of high-resolution crystal structures of complex RNAs have led to new insights into the mechanisms by which these complex folds are attained. In this review the structures of these tertiary motifs and how they influence the folding pathway of biological RNAs are discussed, as well as new developments in modeling RNA structure based upon these findings.