The biosynthesis of glycerides and glycerophosphatides by rabbit reticulocytes

Abstract

1. 1. When rabbit reticulocytes were incubated with [1- 14C]glycerol, radioactivity was incorporated into glycerides and glycerophosphatides but no radioactivity was present in their fatty acid moieties or in cholesterol. 2. 2. Lecithin and ethanolamine phosphatide together contained about 70% and the neutral lipids about 20% of the total radioactivity. The triglyceride, which comprised less than 2% of the lipids, had the highest specific activity of all the lipids. 3. 3. Experiments with other radioactive precursors of the phosphatides gave results which indicate that the minor phosphatides are metabolically much less active than lecithin and that the formation of lecithin from serine phosphatide or ethanol-amine phosphatide is quantitatively unimportant in these cells. 4. 4. Incubation of rabbit reticulocytes with [2- 3H]inositol resulted in the formation of radioactive phosphoinositides. Most of this radioactivity was present in a monophosphoinositide.