Identification and characterization of D-AKAP1 as a major adipocyte PKA and PP1 binding protein.

Department of Biological Sciences, University of Calgary, Calgary, Alta., Canada T2N 4N1.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 08/2006; 346(1):351-7. DOI: 10.1016/j.bbrc.2006.05.138
Source: PubMed

ABSTRACT Protein kinase A (PKA) plays an important role in the regulation of lipid metabolism in adipocytes. The activity of PKA is known to be modulated by its specific location in the cell, a process mediated by A-kinase anchoring proteins (AKAPs). In order to examine the subcellular localization of PKA in this tissue we performed a search for AKAP proteins in adipocytes. We purified a 120 kDa protein which can bind both the regulatory subunit of PKA as well as the catalytic subunit of protein phosphatase 1 (PP1). This protein was found to be enriched in the lipid droplet fraction of primary adipocytes and was identified as D-AKAP1. This protein may play an important role in the regulation of PKA in adipocytes.

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