The G•U wobble base pair -: A fundamental building block of RNA structure crucial to RNA function in diverse biological systems

The G.U wobble base pair is a fundamental unit of RNA secondary structure that is present in nearly every class of RNA from organisms of all three phylogenetic domains. It has comparable thermodynamic stability to Watson-Crick base pairs and is nearly isomorphic to them. Therefore, it often substitutes for G.C or A.U base pairs. The G.U wobble base pair also has unique chemical, structural, dynamic and ligand-binding properties, which can only be partially mimicked by Watson-Crick base pairs or other mispairs. These features mark sites containing G.U pairs for recognition by proteins and other RNAs and allow the wobble pair to play essential functional roles in a remarkably wide range of biological processes.