1b4y

Publication Abstract from PubMed

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.

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^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.