1w86

From Proteopedia

---

Revision as of 21:25, 24 November 2007

proteopedia linkproteopedia link

spinqualitylabelsall models 1w86 Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

SOLUTION STRUCTURE OF AN DSDNA:LNA TRIPLEX

Overview

We have determined the NMR structure of an intramolecular dsDNA:LNA, triplex, where the LNA strand is composed of alternating LNA and DNA, nucleotides. The LNA oligonucleotide binds to the dsDNA duplex in the, major groove by formation of Hoogsteen hydrogen bonds to the purine strand, of the duplex. The structure of the dsDNA duplex is changed to accommodate, the LNA strand, and it adopts a geometry intermediate between A- and, B-type. There is a substantial propeller twist between base-paired, nucleobases. This propeller twist and a concomitant large propeller twist, between the purine and LNA strands allows the pyrimidines of the LNA, strand to interact with the 5'-flanking duplex pyrimidines. Altogether, the triplex has a regular global geometry as shown by a straight helix, axis. This shows that even though the third strand is composed of, alternating DNA and LNA monomers with different sugar puckers, it forms a, seamless triplex. The thermostability of the triplex is increased by 19, degrees C relative to the unmodified DNA triplex at acidic pH. Using NMR, spectroscopy, we show that the dsDNA:LNA triplex is stable at pH 8, and, that the triplex structure is identical to the structure determined at pH, 5.1.

About this Structure

1W86 is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.

Reference

Solution structure of a dsDNA:LNA triplex., Sorensen JJ, Nielsen JT, Petersen M, Nucleic Acids Res. 2004 Nov 18;32(20):6078-85. Print 2004. PMID:15550567

Page seeded by OCA on Sat Nov 24 23:32:36 2007