Targets the cAMP-dependent protein kinase (PKA) to the plasma membrane, and permits functional coupling to the L-type calcium channel. The membrane-associated form reduces epithelial sodium channel (ENaC) activity, whereas the free cytoplasmic form may negatively regulate ENaC channel feedback inhibition by intracellular sodium (By similarity). Binds cAMP-dependent protein kinase (PKA). Interacts with PRKCA; only the cytoplasmic form is capable of interacting with PRKCA (By similarity).