title: Identification of cGMP-dependent protein kinase anchoring proteins (GKAPs).
abstract: To promote both efficiency and selectivity, many protein kinases and phosphatases are maintained in specific subcellular microenvironments through their association with anchoring proteins. In this study, we describe a new class of proteins, called GKAPS, that specifically bind the Type II cGMP-dependent protein kinase (PKG). GKAPs were detected in rat aorta, brain, and intestine using a protein overlay technique. The PKG binding proteins were distinct from AKAPs, proteins known to bind the cAMP-dependent protein kinase (PKA). Furthermore, a synthetic peptide that blocks association of PKA with AKAPs did not affect the PKG-GKAP interaction. Deletion mutagenesis was used to map the GKAP binding determinants within PKG to the N-terminal regulatory region. While most GKAPs were tissue-specific, a ubiquitous PKG-binding protein was detected and identified as myosin. Analysis of myosin fragments revealed that PKG binds within Subfragment 2. The results define a novel class of anchoring proteins that may target PKG for specific functional roles.
authors.affiliation: Neurological Sciences Institute, Oregon Health Sciences University, Portland 97209, USA.
authors.forename: N K
authors.initials: NK
authors.lastname: Vo
authors.forename: J M
authors.initials: JM
authors.lastname: Gettemy
authors.forename: V M
authors.initials: VM
authors.lastname: Coghlan
mesh_terms: D000818:Animals; D001011:Aorta / Q000737:chemistry; D001665:Binding Sites; D001923:Brain Chemistry; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases; D004252:DNA Mutational Analysis; D007422:Intestines / Q000737:chemistry; D008958:Models, Molecular; D009218:Myosins / Q000302:isolation & purification / Q000378:metabolism*; D009419:Nerve Tissue Proteins; D011485:Protein Binding; D051381:Rats; D000074407:SAP90-PSD95 Associated Proteins; D017384:Sequence Deletion; D014018:Tissue Distribution
chemical_list: D002352:Carrier Proteins; D009419:Nerve Tissue Proteins; D000074407:SAP90-PSD95 Associated Proteins; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases; D009218:Myosins