CHIR-98014S2745

CHIR-98014 inhibits human GSK-3β with K_i of 0.87 nM. CHIR-98014 is very effective in preventing murine and rat GSK-3. Although CHIR-98014 acts as a simple competitive inhibitor of ATP binding, it displays from 500-fold to >1000-fold selectivity for GSK-3 versus 20 other protein kinases including Cdc2, ERK2, Tie-2 and KDR. CHIR-98014 prevents Cdc2 with IC50 of 3.7 μM. However, CHIR 98014 reveals similar ptoency against the highly homologous ɑ and β isoforms of GSK-3, it is noteworthy that it stronly discriminated between GSK-3 and its closest homologs CDC2 and ERK2. Exposure of insulin receptor-expressing CHO-IR cells or primary rat hepatocytes to increasing concentrations of inhibitor CHIR98014 results in a two- to three-fold stimulation of the GS activity ratio above basal. The concentrations of CHIR-98014 giving rise to half-maximal GS stimulation (EC50) is 106 nM and 107 nM for CHO-IR and rat hepatocytes, respectively. ^[1]