1j8g

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spinqualitylabelsall models 1j8g, resolution 0.61Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

X-ray Analysis of a RNA Tetraplex r(uggggu)4 at Ultra-High Resolution

Overview

Four-stranded guanine tetraplexes in RNA have been identified to be, involved in crucial biological functions, such as dimerization of, retroviral RNA, translational repression, and mRNA turnover. However, the, structural basis for these biological processes is still largely unknown., Here we report the RNA tetraplex structure (UGGGGU)(4) at ultra-high, resolution (0.61 A). The space group is P42(1)2, and cell constants are a, = b = 36.16 A and c = 74.09 A. The structure was solved by the, multiple-wavelength anomalous dispersion method using a set of, three-wavelength data of the isomorphous bromo derivative (br)UGGGGU and, refined to 0.61-A resolution. Each of the four strands in the asymmetric, unit forms a parallel tetraplex with symmetry-related molecules. The, tetraplex molecules stack on one another in opposite polarity, (head-to-head or tail-to-tail) to form a pseudocontinuous column. All of, the 5'-end uridines rotate around the backbone of G2, swing out, and form, unique octaplexes with the neighboring G tetraplexes, whereas the 3'-end, uridines are stacked-in and form uridine tetrads. All of the bases are, anti, and the riboses are in the mixed C2'- and C3'-puckering mode., Strontium ions are observed in every other guanine tetrad plane, sitting, on the fourfold axis and associated to the eight O6 atoms of neighboring, guanine bases in a bipyramidal-antiprism geometry. The hydrogens are, clearly observed in the structure.

About this Structure

1J8G is a Protein complex structure of sequences from [1] with SPM, SR, CA and NA as ligands. Full crystallographic information is available from OCA.

Reference

X-ray analysis of an RNA tetraplex (UGGGGU)(4) with divalent Sr(2+) ions at subatomic resolution (0.61 A)., Deng J, Xiong Y, Sundaralingam M, Proc Natl Acad Sci U S A. 2001 Nov 20;98(24):13665-70. Epub 2001 Nov 13. PMID:11707581

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