Mechanistic Studies on Photoinduced Cross-Linking and Specific Cleavage at Guanine by Dibenzoyldiazomethane-Oligodeoxynucleotide Conjugate

Photoirradiation of dibenzoyldiazomethane-oligodeoxynucleotide (DBDM-ODN) conjugate, 5′-DBDM-(CH2)6-d(AAAAAGGGAAGGAAA)-3′ 3, in the presence of 23-mer ODN, 5′-d(TTTCCTTCCCTTTTTG16TTG19TG21TT)-3′ ODN1, having a complementary sequence, induced cross-links of both oligomers. By hot piperidine treatment, the specific cleavage of target ODN1 at G16 was observed. The photo-cross-linked ODNs were purified by electrophoresis on polyacrylamide gel. Upon hot piperidine treatment of the isolated cross-linked ODNs, both the G16 cleavage band and the band of reverted ODN1 were observed.