The ID2 promoter is transactivated by PML-RARα but not by RARα/RXR. (A) Cells were transiently transfected with a 812-bp ID2-luciferase reporter construct (ID2-luc). Transfections and controls were as described in Figure 2. Background luminescence of the cells transfected with only a reporter construct (no nuclear receptor and no ATRA) was set at 1. Transactivation was measured after treatment without (□) and with (■) 10−6 M ATRA. Mean values from at least 3 independent experiments plus or minus SD are shown. (B) Dominant-negative NF-Y (Yam29) inhibits the transactivation of the ID2 promoter construct by PML-RARα. Transfections were done as described in Figure 2; mean values of 3 independent experiments plus or minus SD are shown. (C) Promoter region of the ID2 gene with putative Sp1- and NF-Y–binding sites.
