Live-Cell FRET Imaging of Phosphorylation-Dependent Caveolin-1 Switch.

The detection of dynamic conformational changes in proteins in live cells is challenging. Live-cell FRET (Forster Resonance Energy Transfer) is an example of a noninvasive technique that can be used to achieve this goal at nanometer resolution. FRET-based assays are dependent on the presence of fluorescent probes, such as CFP- and YFP-conjugated protein pairs. Here, we describe an experimental protocol in which live-cell FRET was used to measure conformational changes in caveolin-1 (Cav-1) oligomers on the surface of plasmalemma vesicles, or caveolae.