Table 1.

The effects of ORF50 and HDAC1 cotransfection and TSA treatment of 293T cells on the transcriptional activation function of ORF50 and ORF50 deletion mutantsa

Expression plasmid transfectedRelative luciferase activity
No addition+ TSA+ TSA/no addition+ HDAC1+ HDAC1/no addition
Gal410.940.941.51.50
Gal4/ORF504,1928,5622.041,0900.26
Gal4/N6724,5489,3332.051,2400.27
Gal4/N6262,9625,9332.006070.20
Gal4/N5997.8303.8430.38
Gal4/N5895.5441.25.772.50.45
Gal4/N4498.42424.9930.36
Gal4/N2993.542.720.773.981.12
Gal4/N2462.543.11.223.321.31
Gal4/C301-6912,5006,2502.57500.3
Gal4/C581-6915465000.925390.99
Gal4/C607-6912402050.852551.06
Gal4/LXXAA1,240b
  • a A luciferase reporter gene with Gal4 binding sites was cotransfected with a control expression plasmid (Gal4) or an expression plasmid encoding various versions of ORF50 fused to the Gal4 DNA binding domain (10 ng). In some experiments, an expression plasmid encoding HDAC1 (1 μg) was cotransfected (+ HDAC1). Some of the transfected cells were treated with TSA (0.1 μg/ml) (+ TSA). The luciferase activity of each ORF50 mutant was determined. Three independent experiments were performed for each condition, and a representative result is shown for each experiment. The outcomes of all three experiments were very similar. In each case, the activity of Gal4 in the absence of HDAC1 and TSA is normalized to a value of 1.

  • b —, not determined.