Interleukin 3 stimulates phosphatidylcholine turnover in a mast/megakaryocyte cell line

The hemopoietic growth factor, interleukin 3, has been shown to activate protein kinase C without causing hydrolysis of inositol phospholipids. The potential involvement of phosphatidylcholine hydrolysis as an alternative source of diacylglycerol was investigated in an interleukin 3-dependent murine mast/megakaryocyte cell line, R6-XE.4. Treatment of these cells with interleukin 3 rapidly stimulated both the release of water-soluble choline metabolites and the resynthesis of phosphatidylcholine. Therefore, a phosphatidylcholine cycle may operate as part of the signal transduction pathway in cells responding to interleukin 3.