Figure 6.

Possible schemes to screen inhibitors or activators targeting protein–DNA interactions by PDI-ELISA. (A) This screening scheme can be used to identify small molecule inhibitors that upon bind to the DNA-binding proteins cause the protein conformation change and dissociate the protein from the target DNA sequence. (B) Certain transcription factors do not bind to the target DNA sequence in the absence of a small molecule ligand. This screening scheme can be used to identify these small molecule ligands. (C) Certain small molecules or proteins act as activators to help a protein binding to a target DNA sequence. This screening scheme can be used to identify such activators using PDI-ELISA. Please see Figure 1 for the meaning of different symbols.