A-kinase anchor protein 5 (AKAP5), also known as AKAP79, is a PKA anchoring protein that binds to adenylyl cyclase type 8 (AC8) and to regulate its responsiveness to store-operated Ca(2) entry (SOCE) []. The AKAP79 and AC8 interaction may occur in lipid raft domains of the plasma membrane, with palmitoylation of AKAP79 plays an important role in targeting the AKAP to the cholesterol- and sphingolipid-rich regions of the plasma membrane where it can impact on local Ca2 -stimulated AC8 activity [].
The AKAP CaM-binding motif (also known as the WSK motif) is short motif, named after three conserved residues found in the WXSXK motif, found in protein kinase A anchoring proteins. The A kinase-anchoring proteins AKAP-5 and AKAP-12 (Gravin) bind calmodulin (CaM), a Ca(2+)-sensing protein that is expressed in all eukaryotic cells and mediates many essential processes driven by Ca(2+), including long-term changes in synaptic connections in the brain, apoptosis, and immune responses. The AKAP CaM-binding motif contains hydrophobic amino acids in a 1-4-7-8 pattern within an helix [].
