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1b4y
From Proteopedia
STRUCTURE AND MECHANISM OF FORMATION OF THE H-Y5 ISOMER OF AN INTRAMOLECULAR DNA TRIPLE HELIX.
Overview
H-DNA, thought to play a regulatory role in transcription, exists in two isomeric forms, H-y3 and H-y5. We present the first solution structure of a DNA fragment representing the H-y5 fold. The structure shows the H-y5 triple helix, and for the first time how in an H-DNA isomer the purine strand extension interacts with the triplex loop. It gives direct insight into the mechanism of H-DNA formation, and explains a host of biochemical and biophysical data on the relative stability of the H-DNA isomers. In addition, the observed interaction of the purine strand extension and the triplex loop provides new clues to the design of clamp-type triple helix-forming oligonucleotides.
About this Structure
Full crystallographic information is available from OCA.
Reference
Structure and mechanism of formation of the H-y5 isomer of an intramolecular DNA triple helix., van Dongen MJ, Doreleijers JF, van der Marel GA, van Boom JH, Hilbers CW, Wijmenga SS, Nat Struct Biol. 1999 Sep;6(9):854-9. PMID:10467098 Page seeded by OCA on Fri May 2 11:04:43 2008
