SpringerProtocols: Abstract: Glycogen Synthase Activity in Adipose Tissue: Methods for Freeze-Clamping and Assay

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Glycogen Synthase Activity in Adipose Tissue: Methods for Freeze-Clamping and Assay

By: Heidi K. Ortmeyer²

Abstract

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One of the best markers of in vivo insulin-action at insulin sensitive tissues is an increase in glycogen synthase (GS) activity. GS is the rate-limiting enzyme of GS. The activity of glycogen synthase is increased by dephosphorylation, which converts the dependent form (dependent on glucose 6-phosphate [G6P]) to the independent form. GS activity can be increased by an increase in the activities of protein (serine/threonine) phosphatases, which dephosphorylate the enzyme, and/or by a decrease in the activities of protein (serine/threo-nine) kinases, which phosphorylate the enzyme.

Affiliation(s): (2) Obesity and Diabetes Research Center, University of Maryland School of Medicine, Baltimore, MD, USA

Book Title: Adipose Tissue Protocols

Series: Methods in Molecular Biology | Volume: 155 | Pub. Date: Mar-01-2001 | Page Range: 89-96 | DOI: 10.1385/1-59259-231-7:089

Subject: Cell Biology

References

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