Figure 7.

Sequence selectivity and cleavage complexes induced by Cs-TopIB, Hs-Top1mt and Hs-Top1 in the absence and presence of Top1 inhibitors. (A) 3′-end ³²P-end labeled pSK-DNA was incubated with Cs-TopIB, Hs-Top1 or Hs-Top1mt at 25°C for 20 min in the presence of the indicated concentrations of CPTs (CPT in μM). Cleavage sites are indicated to the left with corresponding sequences to the right (cleavage indicated by caret). (B) Additional experiments with the catalytic dead (see Supplementary Figures S2–S3) Cs-TopIB-Y477F enzyme compared to the wild-type enzyme and with additional Top1 inhibitors: the indenoisoquinoline LMP744 and the marine alkaloid lamellarin D (LamD).