Figure 3.

TLS of the cisplatin adduct detected on 90-mer by incorporation of [α-³²P]dATP in presence of the 59-mer complementary strand. Nonradioactive primed single-stranded DNA modified site specifically with cisplatin (see Fig. 1A) was replicated for 30 min by cell extracts to allow complete arrest of replication at the site of the adduct, as monitored by a parallel reaction with labeled primer (not shown). Subsequently, the tailed fork was formed by annealing the 59-mer complementary strand and the reaction was continued in the presence of [α-³²P]dATP for 30 min (lane 1). A control reaction without the 59-mer was conducted in parallel (lane 2). Positions of the 68-mer (product of synthesis to the dT base preceding the Pt lesion) and 90-mer (full-size product) are indicated by arrows.