Table 1. DNA substrate constructs used in the present study.

name	sequences	primer length (nts)a
DNA1	5'-GACTACATTTCATCTGGCTTGGGCTTCATCGTTGTCdUfCAGACCTGGTGGATACCG	17
	3'-CTGATGTAAAGTAGACCGAACCCGAAGTAGCAACAG A OTCTGGACCACCTATGGC*
DNA2	5'-GACTACATTTCATCTGGCTTGGGCTTCATCGTTGTCdUfCAGACCTGGTGGATACCG	18
	3'-CTGATGTAAAGTAGACCGAACCCGAAGTAGCAACAG O GTCTGGACCACCTATGGC*
DNA3	5'-GACTACATTTCATCTGGCTTGGGCTTCATCGTTGTCdUfCAGACCTGGTGGATACCG	19
	3'-CTGATGTAAAGTAGACCGAACCCGAAGTAGCAACAO A GTCTGGACCACCTATGGC*
DNA4	5'-GACTACATTTCATCTGGCTTGGGCTTCATCGTTGTCTCAGACCTGGTGGATACCG	18
	3'-CTGATGTAAAGTAGACCGAACCCGAAGTAGCAACAGOGTCTGGACCACCTATGGC*

^aprimer length – the length of the primed oligonucleotide created under hAPE1 activity, dU^f –5-formyl-2'-deoxyuridine, O – AP site, * –³²P-radioactive label.