Schematic diagrams of RIα regions subjected to in vitro binding assays. Results from the RIα-SPATC1L interaction assay (Fig. 3B) are indicated as + or - at right. D/D, dimerization/docking domain (binding site for AKAPs); Domain A, catalytic subunit binding domain and cAMP binding domain; Domain B, cAMP binding domain; IS, inhibitor sequence (binding site for the active site of the catalytic subunit). 