Figure 2. Concept of the link between choline metabolism and intracellular signaling. A proposed concept of how EDI3 links choline metabolism to altered signaling network activities. Choline is further metabolized to the major membrane lipid PtdC. Tumor cells have a higher demand for this lipid to facilitate restructuring of the cell membrane for division and migration. G3P fuels the G3P-LPA-PA-DAG pathway which creates anchoring points for GTPases and PKC and activates intracellular signaling (from Marchan et al., 2012). Abbreviations: CDP-Cho, cytidine 5′-diphosphocholine; CHK, choline kinase; CT, CDP, phosphocholine cytidyltransferase; DAG, diacylglycerol; DAGK, DAG kinase; G3P, glycerol-3-phosphate; LPL, lysophospholipase; GPAT, G3P acyltransferase; LPAAT, LPA acyltransferase; PAP, PA phosphatase; PCT, diacylglycerol choline phosphotransferase; PLA, phospholipase A; PLB, phospholipase B; PLC, phospholipase C; PLD, phospholipase D; PtdC, phosphatidylcholine (from Marchan et al., 2012).²²