AKAP18:PKA-RIIα structure reveals crucial anchor points for recognition of regulatory subunits of PKA.
A-kinase anchoring proteins (AKAPs) interact with the dimerization/docking (D/D) domains of regulatory subunits of the ubiquitous protein kinase A (PKA). AKAPs tether PKA to defined cellular compartments establishing distinct pools to increase the specificity of PKA signalling. Here, we elucidated the structure of an extended PKA-binding domain of AKAP18β bound to the D/D domain of the regulatory RIIα subunits of PKA. We identified three hydrophilic anchor points in AKAP18β outside the core PKA-binding domain, which mediate contacts with the D/D domain. Such anchor points are conserved within AKAPs that bind regulatory RII subunits of PKA. We derived a different set of anchor points in AKAPs binding regulatory RI subunits of PKA. In vitro and cell-based experiments confirm the relevance of these sites for the interaction of RII subunits with AKAP18 and of RI subunits with the RI-specific smAKAP. Thus we report a novel mechanism governing interactions of AKAPs with PKA. The sequence specificity of each AKAP around the anchor points and the requirement of these points for the tight binding of PKA allow the development of selective inhibitors to unequivocally ascribe cellular functions to the AKAP18-PKA and other AKAP-PKA interactions.
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany Leibniz Institute for Molecular Pharmacology (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Frank
F
Götz
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Yvette
Y
Roske
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Maike Svenja
MS
Schulz
Department of Biochemistry, University of Kassel, Heirnich-Plett-Str. 40, 34132 Kassel, Germany.
Karolin
K
Autenrieth
Department of Biochemistry, University of Kassel, Heirnich-Plett-Str. 40, 34132 Kassel, Germany.
Daniela
D
Bertinetti
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Katja
K
Faelber
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Kerstin
K
Zühlke
Leibniz Institute for Molecular Pharmacology (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Annika
A
Kreuchwig
Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 240 W. Green St., Athens, GA 30602, U.S.A.
Eileen J
EJ
Kennedy
Leibniz Institute for Molecular Pharmacology (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Gerd
G
Krause
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Oliver
O
Daumke
Department of Biochemistry, University of Kassel, Heirnich-Plett-Str. 40, 34132 Kassel, Germany.
Friedrich W
FW
Herberg
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany.
Udo
U
Heinemann
Max Delbrück Centre for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany DZHK, German Centre for Cardiovascular Research, Oudenarder Straße 16,13347 Berlin, Germany enno.klussmann@mdc-berlin.de.
Enno
E
Klussmann
D054758:A Kinase Anchor Proteins / Q000737:chemistry* / Q000378:metabolism*; D000595:Amino Acid Sequence; D001665:Binding Sites; D002151:Calorimetry; D017868:Cyclic AMP-Dependent Protein Kinases / Q000737:chemistry* / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D047468:Immunoprecipitation; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D015398:Signal Transduction; D020349:Surface Plasmon Resonance
D054758:A Kinase Anchor Proteins; D021122:Protein Subunits; D017868:Cyclic AMP-Dependent Protein Kinases
A-kinase anchoring protein; D/D domain; PKA-binding domain; compartmentalized cAMP signalling; protein kinase A; protein–protein interaction