IC261

A cell-permeable, reversible, potent and selective inhibitor of Casein Kinase (CK1) that inhibits the CK1δ (IC₅₀ = 0.7-1.3 µM) and CK1ε (IC₅₀ = 0.6-1.4 µM) isozymes. Also inhibits CK1α₁ at much higher concentrations (IC₅₀ = 11-21 µM). The inhibition is competitive with respect to ATP. Has only a trivial effect on p34^cdc2 and p55^fyn (IC₅₀s >100 µM). Blocks the phosphorylation of p53 by CK1δ and CK1ε, thereby modulating p53′s effect on the cell cycle. At low micromolar concentrations, IC261 inhibits cytokinesis causing a transient mitotic arrest.

Cell permeable: yes

Primary Target
CK1δ

Product competes with ATP.

Reversible: yes

Target IC₅₀: 0.7-1.3 µM, 0.6-1.4 µM, against CK1δ and CK1ε isozymes, respectively

Packaged under inert gas

Following reconstitution, aliquot, purge with inert gas, and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C when stored under an inert gas.

Behrend, L., et al. 2000. Oncogene19, 5303.
Mashhoon, N., et al. 2000. J. Biol. Chem.275, 20052.
Knippschild, U., et al. 1997. Oncogene15, 1727.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Toxicity: Standard Handling (A)