The physical state of the MfPV genomes during transient DNA replication in U2OS cells.

U2OS cells were transfected with 4 μg E8^E2C mutant minicircle DNA of MfPV1 (lanes 1–3), MfPV5 (lanes 4–6), and MfPV8 (lanes 7–9). LMW DNA extracted via Hirt lysis 3, 4 and 5 days posttransfection (shown on the top), the samples were treated with DpnI, and analyzed by Southern blotting. Abbreviations: oc, open circular molecules; ccc, covalently closed circular molecules; lin, linear molecules; the numbers 1 and 2 refer to monomers and dimers, respectively.