title: Base pairs and pseudo pairs observed in RNA-ligand complexes.
abstract: Previously, a geometric nomenclature was proposed in which RNA base pairs were classified by their interaction edges (Watson-Crick, Hoogsteen or sugar-edge) and the glycosidic bond orientations relative to the hydrogen bonds formed (cis or trans). Here, base pairs and pseudo pairs observed in RNA-ligand complexes are classified in a similar manner. Twenty-one basic geometric families are geometrically possible (18 for base pairs formed between a nucleic acid base and a ligand containing heterocycle and 3 families for pseudo pairs). Of those, 16 of them have been observed in X-ray and/or NMR structures.
authors.affiliation: Architecture et Réactivité de l'ARN, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, CNRS, 15 rue René Descartes, 67084 Strasbourg, France.
authors.forename: Jiro
authors.initials: J
authors.lastname: Kondo
authors.forename: Eric
authors.initials: E
authors.lastname: Westhof
mesh_terms: D020029:Base Pairing; D018360:Crystallography, X-Ray; D030562:Databases, Protein; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D009690:Nucleic Acid Conformation; D012313:RNA / Q000737:chemistry*
chemical_list: D008024:Ligands; D012313:RNA