Cell-permeable. CHIR-98014 is a potent, selective and ATP-competitive inhibitor of GSK3α and GSK3β (IC₅₀ = 0.65 and 0.58 nM, respectively). In addition, CHIR-98014 displays 500 to greater than 1000-fold selectivity towards GSK3 than other protein kinases such as cdc2 and ERK2. CHIR98014 also reduces tau phosphorylation in rat brains and supports Wnt signaling during osteogenesis.