Modulation of remote DNA oxidation by hybridization with peptide nucleic acids (PNA) Original Research Article

We have examined the efficiency of DNA photooxidation in DNA/PNA duplex and DNA/(PNA)2 triplex for the first time. DNA/PNA duplex was cleaved at GG steps by external riboflavin with high efficiency like specific GG cleavage in DNA/DNA duplex. However, the 5′G selectivity of the GG oxidation in DNA/PNA duplex was much lower than that observed in DNA/DNA duplex. Remote DNA oxidation of oxidant-tethered DNA/PNA duplex was considerably suppressed. In contrast, the formation of DNA/(PNA)2 triplex by hybridization with two PNA strands completely inhibited the remote GG oxidation, indicating that PNA acts as an inhibition for remote oxidative DNA damage.