Phorbol esters, phospholipase C, and growth factors rapidly stimulate the phosphorylation of a Mr 80,000 protein in intact quiescent 3T3 cells

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摘要：

Addition of biologically active phorbol esters to intact quiescent 3T3 mouse cells stimulates an extremely rapid (detectable within seconds) phosphorylation of a Mr80,000 cellular protein (termed ``80k''). Phorbol 12, 13-dibutyrate enhances 80k phosphorylation in a dose-dependent manner; half-maximal effect is obtained at 32 nM. The possibility that this phosphorylation is related to the activation of Ca2+-activated phospholipid-dependent protein kinase is suggested by the fact that phospholipid breakdown induced by exogenous treatment of the cells with phospholipase C from Clostridium perfringens or with platelet-derived growth factor, which is a potent activator of endogenous phospholipase C activity, also causes a rapid enhancement of 80k phosphorylation. Moreover, prolonged pretreatment of the cells with phorbol 12, 13-dibutyrate, which leads to a marked decrease in the number of specific phorbol ester binding sites, prevents the phosphorylation of 80k stimulated by phorbol esters, phospholipase C, and platelet-derived growth factor. These findings provide evidence obtained with intact cells that implicate the stimulation of Ca2+-activated phospholipid-dependent protein kinase in the action of phorbol esters and other growth factors.

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关键词：

Cell Biology Ca2+-activated Phospholipid-Dependent Protein Kinase Platelet-Derived Growth Factor Phorbol Ester Receptors Tumor Promoters

DOI：

10.1073/pnas.80.23.7244

被引量：

1205

年份：

1983