FIG. 4.

Autoradiograph of a transient DNA replication assay. SCC-13 cells were transfected with plasmid CRPV-pGL3-NCR either alone (−) or together with an expression vector for CRPV E1 and an expression vector for CRPV wt E2 or the R37K, R37A, E39Q, E39A, I73L, or I73A mutant E2 protein. Low-molecular-weight DNA was extracted, digested with DpnI and HpaI, and analyzed by Southern blot hybridization. The position of DpnI-resistant CRPV-pGL3-NCR DNA is indicated by an arrow. Percentages given refer to the amounts of replicating plasmids of the respective E2 mutants in relation to the wt E2 protein (100%).