Figure 2.

Gardella gel analysis of individual, hygromycin-resistant B95.8 cell clones that were generated after transfection of the linearized F factor plasmid DNA shown in Fig. 1. After Southern blotting the blot was probed with an F factor-specific probe. Four of seven hygromycin-resistant cell lines showed clear signals, indicating a successful recombination between endogenous, wild-type B95.8 DNA molecules and the transfected linearized plasmid DNA carrying the F factor replicon. The two discrete bands correspond to the circular and linear forms of the B95.8/F factor DNA molecules. Linear EBV molecules are indicative of spontaneous lytic EBV replication, which is common in B95.8 cells.