The present invention provides a new monomer for preparation of peptide nucleic acid (PNA) carrying a novel 2-aminopyridine nucleobase.
PNAs containing 2-aminopyridine and other modified nucleobases form stable and sequence selective triple helices with double-stranded RNA at physiologically relevant conditions. The modified PNAs display unique RNA selectivity by having two orders of magnitude higher affinity for the double-stranded RNAs than for the same DNA sequences. Results show that nucleobase-modified PNA bind and recognize complex biologically important RNAs, such as double helical precursors of microRNAs.
• Ability to recognize double helical RNA in a sequence selective manner at physiologically relevant conditions.
• Strong and selective triple helical binding of peptide nucleic acids to double-stranded RNA.