Enhancing DNA Triple Helix Stability at Neutral pH by the Use of Oligonucleotides Containing a More Basic Deoxycytidine Analog

Abstract

DNA triple helices in the parallel binding motif can efficiently be stabilized at neutral pH by replacing deoxycytidine in the third strand by the C-nucleoside 1. The increase in stability is due to the higher pKa of the base in 1, rendering its protonation, required for base pair formation, more favorable at physiological pH.