AKAP9 Gene - A-Kinase Anchoring Protein 9 | Function, Mutations & Disease

AKAP9 (A-kinase anchoring protein 9) encodes a scaffold protein that anchors protein kinase A (PKA) and other signaling enzymes to specific subcellular compartments, including the centrosome and Golgi apparatus. It plays a critical role in regulating cardiac ion channels, particularly the potassium channel KCNQ1, and is essential for normal cardiac repolarization. Mutations in AKAP9 are associated with long QT syndrome and other arrhythmias. The protein also participates in microtubule organization and cell cycle progression.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Adrenergic signaling in cardiomyocytes (KEGG: hsa04261)

• cGMP-PKG signaling pathway (KEGG: hsa04022)

• PKA-mediated phosphorylation of KCNQ1 (Reactome: R-HSA-5576892)

• Centrosome maturation (Reactome: R-HSA-380270)

AKAP9 is a large scaffold protein (approximately 390 kDa) that localizes to centrosomes, Golgi, and plasma membrane. It contains multiple PKA-binding domains, a targeting domain for centrosomal localization, and interacts with ion channels such as KCNQ1. Through its anchoring function, AKAP9 coordinates PKA phosphorylation of substrates involved in cell cycle, microtubule dynamics, and cardiac action potential. The protein also binds other kinases (PKC, PKN) and phosphatases, integrating diverse signaling inputs.