2ab5

Publication Abstract from PubMed

LAGLIDADG endonucleases bind across adjacent major grooves via a saddle-shaped surface and catalyze DNA cleavage. Some LAGLIDADG proteins, called maturases, facilitate splicing by group I introns, raising the issue of how a DNA-binding protein and an RNA have evolved to function together. In this report, crystallographic analysis shows that the global architecture of the bI3 maturase is unchanged from its DNA-binding homologs; in contrast, the endonuclease active site, dispensable for splicing facilitation, is efficiently compromised by a lysine residue replacing essential catalytic groups. Biochemical experiments show that the maturase binds a peripheral RNA domain 50 A from the splicing active site, exemplifying long-distance structural communication in a ribonucleoprotein complex. The bI3 maturase nucleic acid recognition saddle interacts at the RNA minor groove; thus, evolution from DNA to RNA function has been mediated by a switch from major to minor groove interaction.

Evolution from DNA to RNA recognition by the bI3 LAGLIDADG maturase.,Longo A, Leonard CW, Bassi GS, Berndt D, Krahn JM, Hall TM, Weeks KM Nat Struct Mol Biol. 2005 Sep;12(9):779-87. Epub 2005 Aug 21. PMID:16116439^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.