Diacylglycerol - when is it an intracellular messenger?

Distinct, structurally different forms of sn-1,2-diacylglycerol are found i n cells, these are polyunsaturated, mono- or diunsaturated and saturated. T he pathways that generate or metabolise sn-1,2-diacylglycerol are reviewed. The evidence that it is the polyunsaturated forms of sn-1,2-diacylglycerol ,but the more saturated forms of phosphatidate which function as intracellu lar signals is considered. (C) 1998 Elsevier Science B.V. All rights reserv ed.