FIG. 4.

The CREB transcription factor binding site upstream of two SP1 sites has the greatest effect on early viral gene expression. Transfection of HCMV Towne BAC DNAs and the measurement of either IE1/IE2 RNA, UL44 early RNA, CAT activity, or viral DNA were as described in Materials and Methods. (A) Quantitative RT-PCR of IE1/IE2 RNA at 10 days after transfection (d p.t.). (B) Quantitative RT-PCR of UL44 RNA at 10 days posttransfection. (C) Viral gene expression as measured by CAT activity at various days after transfection. (D) Quantitative PCR of gB DNA at various days after transfection.