Send to

Choose Destination
Biochem Biophys Res Commun. 1989 Mar 15;159(2):548-53.

Calphostin C (UCN-1028C), a novel microbial compound, is a highly potent and specific inhibitor of protein kinase C.

Author information

Tokyo Research Laboratories, Kyowa Hakko Kogyo Co. Ltd., Japan.


Calphostin C (UCN-1028C), a newly isolated compound from Cladosporium cladosporioides, is a potent and specific inhibitor of protein kinase C, because it was 1000 times more inhibitory to protein kinase C (IC50, 0.05 microM) than other protein kinases such as cAMP-dependent protein kinase and tyrosine-specific protein kinase (IC50, greater than 50 microM). Calphostin C did not inhibit calcium activated neutral protease (calpain)-digested protein kinase C, indicating that it interacts with the regulatory domain of protein kinase C. In addition this compound showed inhibitory effects on the binding of [3H]PDBu to protein kinase C. The potent cytotoxic activity and antitumor activity of calphostin C might be due to the inhibition of protein kinase C, and thus it may be potentially useful for the therapeutic application.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center