CFTR is situated in nanoscale liquid ordered regions of the plasma membrane called lipid rafts that fuse to form large ceramide-rich platforms in response to many types of cell stress and when secretion is stimulated by physiological agonists. CFTR interacts both physically and functionally with other proteins at the cell surface. We want to know if those interactions depend on the nature of the microdomain and how they are altered when CFTR is stimulated.