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. Fig, 1: Scheme of the homologous recombination strategy used to inactivate the POLH (A) or the REV3L gene (B)

. Kbp, Scale bars are 5 kbp wide. (a): constructs used to inactivate POLH in the wild-type BL2 cell line

. Fig, 2: Cell cycle analysis in polymerase-deficient cell lines