Formation and Repair of Tobacco Carcinogen-Derived Bulky DNA Adducts

Figure 1

Schematic presentation of the formation, repair and mutagenic potential of tobacco carcinogen-induced bulky adducts in genomic DNA. The formation of a bulky DNA adduct (marked in red), if not repaired or poorly repaired, results in multiple genetic changes such as cell death and gene mutation. TLS (translesion DNA synthesis) can prevent a mutation by error-free incorporation opposite the adduct. Error-prone incorporation at the adduct site by replicative or translesional DNA pols is the source for mutation. Only those adducts that finally escape all the defense mechanisms may lead to biologically important mutations.