Staurosporine, an alkaloid produced in Streptomyces staurospores originally as an antifungal agent, is an inhibitor of a broad spectrum of protein kinases, including protein kinase C (PKC), Camp-dependent protein kinase (PKA), phosphorylase kinase, ribosomal protein S6 kinase, epidermal growth factor receptor (EGF-R) kinase and Ca2+/calmodulin-dependent protein kinase II (Ca/CaM PKII). The inhibition potency is strongest for PKC (IC50 = 2.7 nM) but several-fold lower for other protein kinases. Staurosporine exhibits a strong cytotoxicity to some mammalian tumor cell lines, induces cell apoptosis, and arrests fission yeast cell elongation specifically at a stage immediately after cell division.
Reference
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