A three-dimensional model of the Rev-binding element of HIV-1 derived from analyses of aptamers

Coordinated variations in the sequence of the Rev-binding element of HIV-1, identified by in vitro genetic selections, have been used as distance and conformational constraints for molecular modelling. Three-dimensional models of the wild-type Rev-binding element and several, evolved RNA ligands (aptamers) have been constructed. These models demonstrate that non-Watson-Crick pairings open the major groove allowing access of an alpha-helical peptide from Rev, and explain why some selected RNA sequences can bind Rev more tightly than others.