Dimerization assay

A method for screening for an inhibitor of association between first and second candidate binding partners, the method comprising:

• providing a cell, wherein the cell comprises:
• a test compound;
• a first hybrid protein comprising a first component of a DNA-binding protein linked to the first candidate binding partner;
• a second hybrid protein comprising a second component of the DNA-binding protein linked to the second candidate binding partner;
• and
• a reporter expression cassette that encodes a reporter expression product, wherein the first and second hybrid proteins form a DNA-binding complex upon association of the first and second candidate binding partners, and wherein the reporter expression cassette comprises at least one binding site for the DNA-binding complex such that binding of the complex to the binding site inhibits expression of the reporter expression product;
• and
• determining expression of the reporter expression product in the presence of the test compound;
• wherein an increase in expression of the reporter expression product in the presence of the test compound indicates that the test compound is capable of inhibiting association between the first and second candidate binding partners.