GSK-3

Glycogen synthase kinase-3 (GSK-3) is a highly conserved serine/threonine kinase that regulates diverse cellular processes by phosphorylating a broad range of substrates involved in metabolism, transcription, cell fate determination, and signal transduction pathways^[1][2]. GSK-3 functions as a central signaling node in pathways including Wnt/β-catenin and PI3K/Akt, where its activity influences cellular homeostasis and coordinates anabolic and catabolic responses^[1][3]. Mechanistically, Akt-mediated phosphorylation inhibits GSK-3 activity, thereby regulating downstream targets associated with glycogen metabolism, gene expression, and cell survival^[2]. Dysregulated GSK-3 signaling has been implicated in multiple pathological conditions, including neurodegenerative disorders, psychiatric diseases, inflammatory disorders, diabetes, and cancer, highlighting its broad disease relevance and experimental value^[1][2][4]. In disease models, elevated GSK-3 activity has been linked to neuroinflammation, neurodegeneration, and cognitive dysfunction, supporting its role as a mechanistic driver of pathological signaling networks^[2][5]. Compared with related isoforms, GSK-3α and GSK-3β are encoded by distinct genes and share highly conserved catalytic domains while exhibiting differences in their N- and C-terminal regions, resulting in both overlapping and isoform-specific biological functions^[5][1]. This distinction is particularly important for experimental design because isoform-selective mechanisms may influence disease phenotypes and therapeutic responses^[1]. For experimental applications, numerous GSK-3 inhibitors have been developed and widely utilized to investigate signaling regulation and disease mechanisms, although no GSK-3 inhibitor has yet achieved broad clinical use^[5]. Therefore, GSK-3 remains an important molecular target for mechanistic studies and therapeutic research across multiple disease contexts^[1][5].