The effect of neighboring bases on miscoding properties of N2,3-ethenoguanine.

The miscoding potential of N2,3-ethenoguanine (epsilon G), one of the carcinogen vinyl chloride adducts to DNA bases, has been examined by copying of poly (A, epsilon G) templates with DNA-dependent RNA polymerase and reverse transcriptase. In contrast to the results previously obtained with poly (C, epsilon G) templates where epsilon G acts as G and A, in poly (A, epsilon G) templates epsilon G acts almost exclusively as A. These results suggest that mutagenic potential of epsilon G in vivo can depend on the nature of neighboring bases.