Interested in promotions? | Click here >>
Calyculin A
Activators & Inhibitors

Calyculin A #9902

Western Blotting

Western blot analysis of extracts from Jurkat cells, untreated or treated with Calyculin (0.1 µM for 45 minutes prior to lysis), using P-Thr-Polyclonal #9381. Proteins were separated by 2D electrophoresis prior to blotting.

Learn more about how we get our images
Western Blotting

Western blot analysis of extracts from A431 cells treated with varied concentrations of Okadaic Acid or Calyculin A (30 minutes) using P-Thr-Polyclonal #9381.

Learn more about how we get our images

Calyculin A is supplied as a lyophilized clear film. For 10 µM stock, reconstitute in 1 ml DMSO. Store in aliquots at -20ºC in the dark. Treat cells with 50-100 nM calyculin A for 5-30 minutes. Store in aliquots tightly sealed (unopened) at -20ºC in the dark. See MSDS.

This compound is sold only for use in extremely dilute solutions for biological research. No other use is intended and any other use involves substantial hazards. This compound should never be handled in powder or aerosol form or in any other form susceptible to uncontrolled release in the laboratory, even in very small quantities.


Store at -20°C.

Calyculin A is a more potent phosphatase inhibitor than Okadaic acid (2). As shown by Western blot, treatment of cells with 100 nM Calyculin A for 30 minutes induces threonine phosphorylation, detected by Phospho-Threonine-Polyclonal Antibody #9381. IC50 values for inhibitory activity against PP1 are approximately 2 nM. IC50 values for inhibitory activity against PP2A are approximately 0.5 -1.0 nM.



Molecular Formula:


Calyculin A inhibits the activity of protein phosphatases PP1 and PP2A (1,2). Unlike Okadaic acid, which reduces PP2A activity but has little effect on PP1 activity, Calyculin A inhibits both phosphatases (1). Neither Calyculin A nor Okadaic acid inhibit acid or alkaline phosphatases or phospho- tyrosine protein phosphatases (2).

  1. Resjö, S. et al. (1999) Biochem J 341 ( Pt 3), 839-45.
  2. Ishihara, H. et al. (1989) Biochem Biophys Res Commun 159, 871-7.
For Research Use Only. Not For Use In Diagnostic Procedures.

Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.

News from the Bench

Discover what’s going on at CST, receive our latest application notes and tips, read our science features, and learn about our products.


To Purchase # 9902S

View sizes
Product # Size Price
10 µg $ 82