Application of protein-fragment complementation assays in cell biology

We have developed a general experimental strategy that enables the quantitative detection of dynamic protein-protein interactions in intact living cells, based on protein-fragment complementation assays (PCAs). In this method, protein-protein interactions are coupled to refolding of enzymes from cognate fragments where reconstitution of enzyme activity acts as the detector of a protein interaction. Here we discuss the application of PCA to different aspects of cell biology.