Phorbol esters increase the amount of Ca2+, phospholipid- dependent protein kinase associated with plasma membrane

Andrew S. Kraft, Wayne B. Anderson

Research output: Contribution to journalArticle

981 Scopus citations


Although the biochemical mechanism of action of phorbol ester tumour promoters is not fully understood, it is known that phorbol ester binding to the cell surface causes rapid changes in calcium flux1,2 and phospholipid metabolism3-7. A protein kinase activity has recently been described which is dependent on calcium and acidic phospholipids and is further enhanced by diacylglycerol8-10. Previously, we have observed that phorbol ester treatment of EL4 mouse thymoma cells causes a rapid decrease in cytosolic calcium, phospholipid-dependent protein kinase (Ca, PL-PK) activity, which is mediated through the specific phorbol ester cell-surface receptors identified on EL4 cells11. We now show that treatment of parietal yolk sacs (PYS-2) cells with biologically active 12-O-tetradecanoyl phorbol-13-acetate (TPA) provokes a rapid decrease in cytosolic Ca, PL-PK activity that is accompanied by a significant increase in the amount of Ca, PL-PK activity associated with the plasma membrane fraction. These results suggest that the rapid and tight association of Ca, PL-PK activity with the plasma membrane may be an early event in mediating some of the effects of phorbol esters.

Original languageEnglish (US)
Pages (from-to)621-623
Number of pages3
Issue number5901
StatePublished - Dec 1 1983
Externally publishedYes


ASJC Scopus subject areas

  • General

Cite this