Abstract
Energy storage and release at times of food excess or fasting are carefully coordinated
processes that depend on the appropriate differentiation of mesenchymal stem cells
into mature adipocytes (adipogenesis) forming white adipose tissue (WAT) and on regulatory
signals for storage (lipogenesis) or mobilization (lipolysis) of triacylglycerides
(TAGs) from lipid droplets. It is widely recognized that cAMP signaling via protein
kinase A (PKA) is important both in adipogenesis and for hormonal control and lipolysis
in WAT. A kinase anchoring proteins (AKAPs) target PKA to distinct subcellular compartments
in close proximity to its specific substrates thereby providing spatial and temporal
specificity in the mediation of biological effects controlled by the cAMP-PKA pathway.
This review will provide an updated overview of some of the sites of regulation by
cAMP in adipogenesis and lipolysis and the involvement of AKAPs and highlighting,
as a recent example, the AKAP Optical Atrophy 1 (OPA1) and its role in the phosphorylation
of Perilipin to induce lipolysis.
Key words
fat cell - adipose tissue - stem cells