FIGURE 4.

Cell cycle progression is not dramatically altered in rad17Δ rtt106Δ cells under normal conditions or DNA damage stress. A, cells with defects in the 9-1-1 complex have normal cell cycle progression. B, similar defects in cell cycle progression are observed for rtt106Δ and rad17Δ rtt106Δ cells under normal growth conditions. C, the S phase progression of rad17Δ rtt106Δ cells was not disrupted with treatment of CPT. D, mutant rad17Δ rtt106Δ cells exhibit defects in S phase progression in the presence of MMS. Cells of the indicated genotype were arrested at G₁ phase using α-factor and then released into S phase and the cell cycle in normal medium (A and B) or medium containing the indicated amount of CPT (C) or MMS (D).