Figure 5.
Phosphorylation-dephosphorylation mediated regulation of glycogen synthase kinase 3 β by serotonin and other cellular kinases. Serotonin type-1A (5-hydroxytryptamine [5-HT1A]) receptors activation by agonists as 8-hydroxy-N, N-dipropyl-2-aminotetralin inactivate the enzyme by phosphorylation at serine-9 residues through a series of cascade process involving protein kinase C (PKC), PKA, and Akt pathway, while antagonist (WAY100635) inhibit it. Serotonin type-2 (5-HT2) receptor agonists as 2, 5-dimethoxy-4-iodo-phenylisopropylamine by dephosphorylation activates the enzyme, while antagonists (LY53857) inhibit it[45]