Patent ID: 6555326
Filing Date: 2003-04-29
Classification: G01N

Abstract:
An in vitro fluorescent polarization assay method for characterizing an agent as a ligand of a nuclear hormone receptor, comprising steps:forming an in vitro mixture comprising a purified nuclear hormone receptor, a sensor and a candidate agent, but not a natural coactivator protein of the receptor, the sensor consisting of a peptide comprising the sequence L1X1X2L2L3 (SEQ ID NO: 18) covalently coupled to a directly detectable fluorescent label, wherein L1-L3 are independently selected from hydrophobic amino acids and X1-X2 are independently selected from any amino acid and wherein the peptide provides direct, in vitro ligand-dependent binding to the receptor and is 24 or fewer residues in length, wherein the sensor is at a concentration of less than about 100 nM.; measuring an assay fluorescence polarization of the sensor as an indication of sensor binding to the receptor in the presence of the agent; comparing the assay fluorescence polarization to a corresponding control fluorescence polarization, wherein the control fluorescence polarization provides an indication of sensor binding to the receptor in the absence of the agent, and wherein a greater assay fluorescence polarization than control fluorescence polarization indicates that the agent is a ligand of the receptor.