DNA binding by the GRF domain inhibits NEIL3 ICL unhooking activity.
A, schematic of proteins used in this experiment. B, representative gel for ICL unhooking by WT mNEIL3 against a lagging-strand AP-dA ICL fork substrate. C, ICL unhooking activity of WT, GRFmut, and ΔGRF mNEIL3 proteins against the leading-strand AP-dA ICL fork. D, quantification of data shown in B and C (means ± S.D. for three independent experiments).