Figure 1

GFP-based reporter systems for investigating transcription factor (TF) activation. The DNA response element (RE) to which the TF binds is upstream of a minimal promoter that controls GFP expression (A) No fluorescence is observed in the absence of TF binding, (B) Binding of TF leads to promoter activation and GFP fluorescence, (C) Dynamics of a TF (e.g., NF-κB) is the sum of activation of the TF and the dynamics of GFP expression.