CHIR99021

CHIR99021 is an aminopyrimidine derivative that is an extremely potent inhibitor of GSK3, inhibiting GSK3β (IC₅₀ = 6.7 nM) and GSK3α (IC₅₀ = 10 nM) and functions as a WNT activator. It is the most selective inhibitor of GSK3 reported so far.

DIFFERENTIATION:

• Used in cardiomyocyte differentiation from human embryonic stem (ES) and induced pluripotent stem (iPS) cells (Lian et al.)

MAINTENANCE:

• Maintains undifferentiated mouse ES cells in combination with PD0325901, in the absence of LIF (Ying et al.)
• Maintains human and mouse hematopoietic stem cells in cytokine-free conditions, in combination with rapamycin (Huang et al.)

REPROGRAMMING:

• Enables chemical reprogramming (without genetic factors) of mouse embryonic fibroblasts to iPS cells, in combination with Forskolin, Tranylcypromine, Valproic Acid, 3-Deazaneplanocin A, and E-616452 (Hou et al.)
• Direct lineage reprogramming of fibroblasts to mature neurons, in combination with Valproic Acid, RepSox, Forskolin, SP600125, Gö6983 and Y-27632 (Hu et al.)
• Direct lineage reprogramming of fibroblasts to mature neurons, in combination with Forskolin, ISX-9, SB431542, and I-BET151 (Li et al.)
• Generates mouse-like or "ground state" iPS cells from human and rat somatic cells, in combination with PD0325901 and A83-01 (Li W et al. 2009)