WH-4-023

Lck kinase assays

To determine the inhibitory activity of WH-4-023 against Lck, kinase assays were conducted. The Lck HTRF kinase assay involved ATP-dependent phosphorylation of a biotinylated substrate peptide of gastrin with or without WH-4-023. The final concentration of ATP, gastrin and Lck were 0.5 μM, 1.2 μM and 250 pM, respectively. Buffer were made up as follows: 50 mM HEPES pH=7.5, 2 mM DTT, 5 mM MnCl2, 20 mM MgCl2, 50 mM NaCl, 0.05% BSA. The reaction was quenched and ended by adding 160 μL detection reagent. Detection reagent was prepared as follows: 50 mM Tris, pH=7.5, 3 mM EDTA, 100 mM NaCl, 0.05% BSA, 0.1% Tween-20. Before reading, streptavidin allophycocyanin and anti-phosphotyrosine Ab were added at a final concentration of 0.4 μg/mL and 0.025 nM, respectively. Assay plate was read with excitation at 320 nm and emission at 615 and 655 nm.

Cell lines

Naive human pluripotent cells

Preparation method

The solubility of this compound in DMSO is > 10 mM. General tips for obtaining a higher concentration: Please warm the tube at 37 ℃ for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below -20℃ for several months.

Reacting condition

1 μM

Applications

WH-4-023 is a potent and selective Src and Lck inhibitor with IC50 values of 6 and 2 nM, respectively[1].Naive human pluripotent cells were maintained in media containing WH-4-023. WH-4-023 improves the fraction of viable GFP+ cells. Withdrawal of the WH-4-023 results in a change in morphology and slight decrease of OCT4-DPE-GFP reporter activity[2].

References:

[1]. Martin M W, Newcomb J, Nunes J J, et al. Novel 2-aminopyrimidine carbamates as potent and orally active inhibitors of Lck: synthesis, SAR, and in vivo antiinflammatory activity[J]. Journal of medicinal chemistry, 2006, 49(16): 4981.

[2]. Theunissen T W, Powell B E, Wang H, et al. Systematic Identification of Defined Conditions for Induction and Maintenance of Naive Human Pluripotency[J]. Cell stem cell, 2014, 15(4): 471.