Identification of small molecules affecting p53-MDM2/MDMX interaction by fluorescence polarization

Fluorescence polarization (FP) has become a powerful technique to quantitatively analyze the binding of a small soluble fluorescence-labeled probe to a larger soluble protein and its displacement by other molecules. Here, we describe a detailed protocol to identify small molecules capable of targeting p53-MDM2/MDMX interactions using a fluorescence polarization assay with Rhodamine-labeled p53 peptides.