Calphostin C (UCN-1028C), isolated compound from Cladosporium cladosporioides, is a cell permeable, potent and highly selective inhibitor of protein kinase C (IC50=0.05 uM). Calphostin C has been shown to compete at the DAG binding site and inhibit DGK (DAG kinase, DAGK). Calphostin inhibition of PKC is light dependent. At higher concentrations it inhibits myosin light chain kinase, PKA (cAMP-dependent protein kinase), protein kinase G, c-Src (pp60v-src protein TyK) (tyrosine kinase) and DGK. This compound also inhibits PC-PLD1 and -PLD2 (Phospholipase D1 and D2, PLD1 and PLD2). Calphostin C has been observed to induce apoptotic DNA fragmentation and cell death. This compound has demonstrated the ability to inhibit cardiac L-type Ca2+ channels. It has demonstrated the ability to Inhibit cardiac L-type calcium channel protein inhibitors. Calphostin C is an inhibitor of MYLK, PKA and PKD.