Table 1. Oligonucleotide sequences for DNA substrates (5′ to 3′).

Oligonucleotide, size	Sequence
Helicase primers
22-15A, 37 nt	TTTTTTTTTTTTTTTTTAGGGTTAGGGCATGCACTAC
22-15B, 37 nt	GTAGTGCATGCCCTAACCCTAATTTTTTTTTTTTTTT
Exonuclease primers
TelX, 49 nt	TTTTTTTTTTTTTTTGGTGATGGTGTATTGAGTGGGATGCATGCACTAC
TelY, 49 nt	GTAGTGCATGCATCCCACTCAATACACCATCACCTTTTTTTTTTTTTTT
32-5over, 32 nt	TGACGTGACGACGATCAGGGTACGTTCAGCAG
43-5over, 43 nt	AGTGCAGACTGCTGCTGAACGTACCCTGATCGTCGTCACGTCA

Partial duplex DNA substrates were constructed by annealing appropriate top primer to template oligonucleotide. 22-15A and 22-15B were used to construct the 37 nt fork, TelX and TelY – the 49 nt fork and 32-5over and 43-5over—the 32/43 nt 5′-overhang.