Calphostin C, Cladosporium cladosporioides

A cell permeable, highly specific inhibitor of protein kinase C (IC₅₀ = 50 nM) that interacts with the protein’s regulatory domain by competing at the binding site of diacylglycerol and phorbol esters. Does not compete with Ca²⁺ or phospholipids. At higher concentrations inhibits myosin light chain kinase (IC₅₀ >5 µM), protein kinase A (IC₅₀ >50 µM), protein kinase G (IC₅₀ >25 µM), and p60^v-src (IC₅₀ >50 µM). Induces apoptotic DNA fragmentation and cell death in HL-60 human promyelocytic leukemia cells. Requires brief exposure to light for activation.

Cell-permeable, highly specific inhibitor of protein kinase C (IC₅₀ = 50 nM) that interacts with the protein′s regulatory domain by competing at the binding site of diacylglycerol and phorbol esters. At higher concentrations inhibits myosin light chain kinase (IC₅₀ >5 µM), protein kinase A (IC₅₀ >50 µM), protein kinase G (IC₅₀ >25 µM), and p60^v-src protein tyrosine kinase (IC₅₀ >50 µM). Does not compete with Ca²⁺ or phospholipids. Also induces apoptotic DNA fragmentation and cell death in HL-60 human promyelocytic leukemia cells. Inhibition of PKC is dependent on exposure to light in cell-free systems. Ordinary fluorescent light is sufficient for full activation.

Cell permeable: yes

Primary Target
PKC

Product does not compete with ATP.

Reversible: no

Target IC₅₀: 50 nM against protein kinase C

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C.

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

Toxicity: Standard Handling (A)