TAg expression limits archetype BKPyV replication in RPTE cells. A. RPTE cells were transfected with recircularized archetype (A) or rearranged (R) viral genomes. Total cell protein was harvested 4 dpt and 25 ug of protein was analyzed by Western blotting for the expression of TAg and GAPDH. B. RPTE cells were transfected with recircularized archetype genome and empty vector (−) or BKPyV TAg cDNA. Total cell protein was harvested 4 dpt and 30 μg was analyzed by Western blotting for the expression of TAg, VP1, and GAPDH. C. RPTE cells were transfected with recircularized archetype genome and empty vector (−) or BKPyV TAg cDNA, and low molecular weight DNA was harvested 4dpt. Samples were linearized, digested with DpnI, and analyzed by Southern blotting. Arrow indicates the replicated viral genome. Input DNA is not visible on this exposure. Mock, mock transfection. Lin, linearized BKPyV plasmid control. Lin/DpnI, linearized and DpnI-digested BKPyV plasmid control. The blots shown are representative of three independent experiments.