Structure triplex

Nielsen P.E., Egholm M., Buchardt O. Evidence for (PNA)2/DNA triplex structure upon binding of PNA to dsDNA by strand displacement. J. Md. Recognit. 1994 7 165-170. 

Demidov et al., 1994 Hanvey et al., 1992 Knudsen and Nielsen, 1996 Nielsen et al., 1991). The [PNA]2/ DNA triplex structure stabilizes both the bound PNAs and the single stranded D-loop at the PNA binding site (Nielsen et al., 1991 Lohse and Nielsen, 1999). 

Ganesh, Krishna N., Synthetic Control of DNA Triplex Structure Through Chemical Modifications, 3, 263. 

LNA has frequently been used to stabilise duplex structures, but in triplex structures the effect is mixed. Partial substitution of a DNA TFO by LNA increases triplex stability, whilst complete substitution leads to destabilisation. Optimal stabilisation was found with substitution every 2-3 nucleotides of the TFO. The incorporation of LNA into a G-quadruplex structure was shown to alter the orientation of the quadruplex from antiparallel to parallel. ... 

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