Ceramide-1-phosphate:: a novel regulator of cell activation

Ceramide-1-phosphate (Cer-1-P) is emerging as a novel bioactive sphingolipid. It is formed by phosphorylation of ceramide catalyzed by ceramide kinase, and has been implicated in different cellular processes. Cer-1-P is mitogenic for fibroblasts, blocks apoptosis in macrophages, controls phagocytosis in neutrophils, and mediates inflammatory responses. Only recently have we started to uncover the signaling pathways that are affected by Cer-1-P. Recent work has demonstrated that cytosolic phospholipase A(2) and acid sphingomyelinase are direct intracellular targets of Cer-1-P, and that it may also induce phosphorylation of extracellular signal-regulated kinase-2 and calcium mobilization. These actions of Cer-1-P seem to be cell type-specific. (C) 2004 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.