FIG. 8.

p21 facilitates the dissociation of RFC from an ATP-activated primer recognition complex but not from an ATPγS-activated complex. The complex was first formed in the absence of p21 on the primed BTN3 template DNA-coated beads as described in the legend to Fig. 7. The beads were then washed (0 min; lanes 1) and resuspended in buffer A containing 0.2% NP-40, 5 μM poly(dA)-oligo(dT), and either 1 mM ATP (A and B) or 1 mM ATPγS (C and D); then they were incubated further with 10 pmol of His-p21 (+) (lanes 2 to 4) or without His-p21 (−) (lanes 5 to 7) for the indicated time periods at room temperature (A and C) or 0°C (B and D). Finally, the beads were washed and the bound proteins were analyzed by Western blotting along with standards (S1 to S3) as described in the legend to Fig. 5. The loading reaction in lane 8 of panels B, C, and D contained no RFC.