Coordination of three signaling enzymes by AKAP79, a mammalian scaffold protein.

Vollum Institute, Oregon Health Sciences University, Portland, 97201, USA.
Science (Impact Factor: 31.48). 04/1996; 271(5255):1589-92. DOI: 10.1126/science.271.5255.1589
Source: PubMed

ABSTRACT Multivalent binding proteins, such as the yeast scaffold protein Sterile-5, coordinate the location of kinases by serving as platforms for the assembly of signaling units. Similarly, in mammalian cells the cyclic adenosine 3',5'-monophosphate-dependent protein kinase (PKA) and phosphatase 2B [calcineurin (CaN)] are complexed by an A kinase anchoring protein, AKAP79. Deletion analysis and binding studies demonstrate that a third enzyme, protein kinase C (PKC), binds AKAP79 at a site distinct from those bound by PKA or CaN. The subcellular distributions of PKC and AKAP79 were similar in neurons. Thus, AKAP79 appears to function as a scaffold protein for three multifunctional enzymes.

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