Triple-stranded DNA

Three-stranded DNA or triple-stranded DNA, a DNA consisting of three oligonucleotide triple helix structure by winding around each other. In this structure, one of the yarns, W-shaped, Hoogsteen or reverse Hoogsteen hydrogen bonds with DNA sets. This bond, the double helix consists of a large groove.
For example, a T nucleobases, Watson-Crick base pairing formed by Hoogsteen hydrogen bonds with an AT base pair A pair of establishing creates a Axt (x corresponds to a Hoogsteen base pairs). N-3 position of a protonated cytosine (C + is represented as a) establishing a connection with a GC pair G creates a GXC + couple. This DNA triple spirals formed by Hoogsteen pairings homopürin yarn and consists of two homopirimidin, homopirimdin third helix, which homopürin thread the same direction. (Homopürin and homopirimidin, only the DNA strands is a purine or pyrimidine.)
A third thread Homopürin reverse Hoogsteen bonds also connected to the deuce homopürin-homopirimidin. In this structure, a triple, a TA A certain pair, g is connected to a pair of CG. For that you have to turn down the third yarn bases, homopürin third yarn, yarn homopürin sarmaldaki the opposite direction of the original binary (ie antiparallel).
Three-stranded DNA is depicted for the first time in 1957. E. Then seen as an intermediate product of the reaction RecA'nın coli recombinase enzyme. [] DNA triple role in this process is unknown.
Oligonucleotides form triple connecting structures using DNA double coils and rekombinmasyona laboratory induced mutations, also found to block the transcriptio This method is expected to be used in biotechnology and therapy.