Identification of multiple kinetic populations of DNA-binding proteins in live cells (Biophysical Journal)

Understanding how multi-protein complexes function in cells requires detailed quantitative understanding of their association and dissociation kinetics. Analysis of the heterogeneity of binding lifetimes enables interrogation of the various intermediate states formed during the reaction. Single-molecule fluorescence imaging permits the measurement of reaction kinetics inside living organisms with minimal perturbation. However, poor photo-physical properties of fluorescent probes limit the dynamic range and accuracy of measurements of off rates in live cells.