Critical role of cAMP-dependent protein kinase anchoring to the L-type calcium channel Cav1.2 via A-kinase anchor protein 150 in neurons.
The cAMP-dependent protein kinase (PKA) regulates a wide array of cellular functions. In brain and heart PKA increases the activity of the L-type Ca2+ channel Cav1.2 in response to beta-adrenergic stimulation. Cav1.2 forms a complex with the beta2-adrenergic receptor, the trimeric GS protein, adenylyl cyclase, and PKA wherein highly localized signaling occurs [Davare, M. A., Avdonin, V., Hall, D. D., Peden, E. M., Burette, A., Weinberg, R. J., Horne, M. C., Hoshi, T., and Hell, J. W. (2001) Science 293, 98-101]. PKA primarily phosphorylates Cav1.2 on serine 1928 of the central, pore-forming alpha11.2 subunit. Here we demonstrate that the A-kinase anchor protein 150 (AKAP150) is critical for PKA-mediated regulation of Cav1.2 in the brain. AKAP150 and MAP2B specifically co-immunoprecipitate with Cav1.2 from rat brain. Recombinant AKAP75, the bovine homologue to rat AKAP150, binds directly to three different sites of alpha11.2. MAP2B from rat brain also interacts with these same sites in pull-down assays. Gene disruption of AKAP150 in mice dramatically reduces co-immunoprecipitation of PKA with Cav1.2 and prevents phosphorylation of serine 1928 upon beta-adrenergic stimulation in vivo. These results demonstrate the physiological relevance of PKA anchoring by AKAPs in general and AKAP150 specifically in the regulation of Cav1.2 in vivo.
Hall
Duane D
DD
Department of Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242-1109, USA. duane-hall@uiowa.edu
Davare
Monika A
MA
Shi
Mei
M
Allen
Margaret L
ML
Weisenhaus
Michael
M
McKnight
G Stanley
GS
Hell
Johannes W
JW
D054758:A Kinase Anchor Proteins; D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D020746:Calcium Channels, L-Type / Q000302:isolation & purification / Q000502:physiology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology*; D003598:Cytoskeletal Proteins / Q000302:isolation & purification; D007545:Isoproterenol / Q000494:pharmacology; D051379:Mice; D018345:Mice, Knockout; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009474:Neurons / Q000502:physiology*; D010766:Phosphorylation / Q000187:drug effects; D051381:Rats; D018343:Receptors, Adrenergic, beta-2 / Q000187:drug effects / Q000502:physiology; D012694:Serine / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
D054758:A Kinase Anchor Proteins; D048868:Adaptor Proteins, Signal Transducing; C415703:Akap5 protein, rat; C484293:Akap6 protein, rat; C486537:Akap9 protein, rat; D020746:Calcium Channels, L-Type; D003598:Cytoskeletal Proteins; C419385:L-type calcium channel alpha(1C); D008869:Microtubule-Associated Proteins; D018343:Receptors, Adrenergic, beta-2; D012694:Serine; D017868:Cyclic AMP-Dependent Protein Kinases; D007545:Isoproterenol