Table 1.

Plaque formation on NIH 3T3 cells after transfection of the MCMV BAC plasmids in the absence or presence of pBam25a

Transfection conditionPlaque formation after transfection of BAC plasmid:
BAC plasmid only++++++
Cotransfection of BAC plasmid and pBam25b +++++++
  • a Scoring of the transfections was as follows: +++, 10–20 plaques; ++, 5–10 plaques; +, 1–5 plaques; −, no plaques.

  • b Plasmid pBam25 spans the deletion in theie3-deficient BAC plasmids and encodes the MCMV IE genesie1 and ie3.