Alterations in signaling pathway activity have been implicated in the pathogenesis of Duchenne Muscular Dystrophy (DMD), a degenerative muscle disease caused by a deficiency in the costameric protein dystrophin. Accordingly, the notion of the dystrophin - glycoprotein complex (DGC), and by extension the costamere, as harboring signaling components has received increased attention in recent years. The localization of most, if not all, signaling enzymes to this subcellular region relies on interactions with scaffolding proteins directly or indirectly associated with the DGC. One of these scaffolds is myospryn, a large, muscle - specific protein kinase A (PKA) anchoring protein or AKAP. Previous studies have demonstrated a dysregulation of myospryn expression in human DMD suggesting a connection to the pathophysiology of the disorder. Here we report that dystrophic muscle exhibits reduced PKA signaling activity resulting, in part, from severely mislocalized myospryn and the RIIa regulatory subunit of PKA. Furthermore, we show that myospryn and dystrophin coimmunoprecipate in native muscle extracts and directly interact in vitro. Our findings reveal for the first time abnormalities in the PKA signal transduction pathway and myospryn regulation in dystrophin deficiency.