FIG. 6.
Examination of the signal mediators that affect oriP activity. Shown are the results of a transient replication assay of the oriP plasmid. (A) The p38 MAPK. The oriP plasmid (2 μg), the control plasmid (0.5 μg), LMP1Δ(212-386) (0.25 μg), and the expression plasmid of p38 MAPK or the dominant negative mutant of p38 MAPK, p38AGF (8 μg), were transfected. Total amounts of plasmids were 10.75 μg. The specific inhibitor for SB208350 was added into the culture medium at a concentration of 20 μM. (B) Ras and MEK. The oriP plasmid (2 μg), the control plasmid (0.5 μg), one of the expression plasmids of LMP1 (0.5 μg), c-H-ras (4 μg), the dominant active ras 12Vras (4 μg), or the constitutively active mutant of MEK1, MEK1EE (4 μg), were transfected. Total amounts of plasmids were 6.5 μg. Normalized amounts of DpnI-resistant plasmid are shown at the bottom. Data represent averages of three experiments with standard errors (SE). Two fragments indicated by asterisks are products of replication intermediates.