A-kinase anchoring proteins (AKAPs) bind the regulatory subunits of protein 
kinase A (PKA) and localize the holoenzyme to discrete signaling microdomains in 
multiple subcellular compartments. Despite emerging evidence for a nuclear pool 
of PKA that rapidly responds to activation of the PKA signaling cascade, only a 
few AKAPs have been identified that localize to the nucleus. Here we show a 
PKA-binding domain in the amino terminus of Chd8, and demonstrate subcellular 
colocalization of Chd8 with RII. RII overlay and immunoprecipitation assays 
demonstrate binding between Chd8-S and RIIα. Binding is abrogated upon 
dephosphorylation of RIIα. By immunofluorescence, we identified nuclear and 
perinuclear pools of Chd8 in HeLa cells and rat neonatal cardiomyocytes. We also 
show high levels of Chd8 mRNA in RNA extracted from post-natal rat hearts. These 
data add Chd8 to the short list of known nuclear AKAPs, and implicate a function 
for Chd8 in post-natal rat cardiac development.