Fig. 3.

Abasic lesion bypass by cell-free extracts from human fibroblasts and neuroblastoma under A, Pol β-favoring conditions, and B, Pol α-favoring conditions. Reactions were performed and analyzed as described in Materials and Methods. Cell-free extracts containing 3 μg/reaction of WI38 or 2 μg/reaction of SY5Y or HeLa cells were added to annealed primer template. Left, Primer extension on a normal non-lesion-bearing template; right, primer extension on a template with an abasic site, X. The DNA template sequence is shown on the left of A and B.P, Position of the nonextended primer.