What is the Origin of Glycogen Synthase Kinase-3?

This enzyme was originally discovered and named for its function in regulating glycogen synthesis, where it phosphorylates and inactivates the enzyme glycogen synthase. Subsequent research revealed its extensive involvement in multiple other cellular pathways, including those regulated by steroid and peptide hormones. The term is purely biochemical and descriptive of its primary function.

What is the Mechanism of Glycogen Synthase Kinase-3?

GSK-3 acts as a molecular switch that is typically active in the resting state and is inactivated upon receiving an appropriate signal, such as insulin binding to its receptor. When active, it phosphorylates various substrate proteins, including those involved in gene expression and metabolic pathways, thereby regulating their function. Insulin signaling, for example, leads to the phosphorylation and subsequent inactivation of GSK-3, which in turn promotes glucose uptake and glycogen synthesis.

Glycogen Synthase Kinase-3 ∞ Area

Glycogen Synthase Kinase-3

Meaning

Glycogen Synthase Kinase-3 (GSK-3) is a ubiquitously expressed serine/threonine protein kinase enzyme that plays a central, complex role in numerous intracellular signaling pathways, including those regulating glucose metabolism, cellular survival, and mood stabilization. In the context of hormonal health, it is a key downstream mediator of insulin signaling, where its phosphorylation state dictates its activity. Dysregulation of GSK-3 is implicated in insulin resistance and neurodegenerative processes.