Activator or inhibitor? GSK-3 as a new drug target.

Biochemical pharmacology , Vol. 86, No. 2. , pp. 191-199, doi:10.1016/j.bcp.2013.04.022 Glycogen synthase kinase-3 is a cytoplasmic serine/threonine protein kinase that phosphorylates and inhibits glycogen synthase, thereby inhibiting glycogen synthesis from glucose.

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