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283d
From Proteopedia
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| , resolution 2.300Å | |||||||
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| Ligands: | , , , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
A CURVED RNA HELIX INCORPORATING AN INTERNAL LOOP WITH G-A AND A-A NON-WATSON-CRICK BASE PAIRING
Overview
The crystal structure of the RNA dodecamer 5'-GGCC(GAAA)GGCC-3' has been determined from x-ray diffraction data to 2.3-A resolution. In the crystal, these oligomers form double helices around twofold symmetry axes. Four consecutive non-Watson-Crick base pairs make up an internal loop in the middle of the duplex, including sheared G.A pairs and novel asymmetric A.A pairs. This internal loop sequence produces a significant curvature and narrowing of the double helix. The helix is curved by 34 degrees from end to end and the diameter is narrowed by 24% in the internal loop. A Mn2+ ion is bound directly to the N7 of the first guanine in the Watson-Crick region following the internal loop and the phosphate of the preceding residue. This Mn2+ location corresponds to a metal binding site observed in the hammerhead catalytic RNA.
About this Structure
283D is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
A curved RNA helix incorporating an internal loop with G.A and A.A non-Watson-Crick base pairing., Baeyens KJ, De Bondt HL, Pardi A, Holbrook SR, Proc Natl Acad Sci U S A. 1996 Nov 12;93(23):12851-5. PMID:8917508 [[Category: ]]
Page seeded by OCA on Mon Mar 31 01:45:52 2008
