FIG. 4.

p107 inhibition of E1A 243R-induced PCNA expression is dependent on the RFX1-binding site. HeLa cells were transfected with either wild-type PCNA−87 CAT or −44/−40 CAT reporter plasmid (10 μg), pCMV12S.FS or pCMV12S, and increasing amounts of pCMV107 (0, 2, or 4 μg) or pCMV107DE (0, 2, 4, or 6 μg) expression plasmid. CAT activity was calculated as described in the legend to Fig. 1 and represents the average of three independent experiments performed in duplicate with standard deviations indicated.