1hmh
THREE-DIMENSIONAL STRUCTURE OF A HAMMERHEAD RIBOZYME
OverviewOverview
The hammerhead ribozyme is a small catalytic RNA motif made up of three base-paired stems and a core of highly conserved, non-complementary nucleotides essential for catalysis. The X-ray crystallographic structure of a hammerhead RNA-DNA ribozyme-inhibitor complex at 2.6 A resolution reveals that the base-paired stems are A-form helices and that the core has two structural domains. The first domain is formed by the sequence 5'-CUGA following stem I and is a sharp turn identical to the uridine turn of transfer RNA, whereas the second is a non-Watson-Crick three-base-pair duplex with a divalent-ion binding site. The phosphodiester backbone of the DNA inhibitor strand is splayed out at the phosphate 5' to the cleavage site. The structure indicates that the ribozyme may destabilize a substrate strand in order to facilitate twisting of the substrate to allow cleavage of the scissile bond.
About this StructureAbout this Structure
Full crystallographic information is available from OCA.
ReferenceReference
Three-dimensional structure of a hammerhead ribozyme., Pley HW, Flaherty KM, McKay DB, Nature. 1994 Nov 3;372(6501):68-74. PMID:7969422 Page seeded by OCA on Fri May 2 19:00:55 2008