Fluorescence polarization analysis of protein-DNA and protein-protein interactions

Fluorescence polarization is a powerful technique for characterizing macromolecular associations and can provide equilibrium determinations of protein-DNA and protein-protein interactions. This technique is particularly useful (and better suited than electrophoretic methods) to study low affinity protein-protein interactions. In this review, we have outlined the principles underlying the use of fluorescence polarization to study the assembly of higher order complexes that bind to the CRE. The availability of simple, relatively inexpensive instrumentation means that this technology is no longer only within the realm of the physical biochemist.