 cholineethanolamine kinase Ethanolamine- phosphate cytidylyltransferase phosphatidylserine synthase phosphatidylserine decarboxylase cholineethanolaminephosphotransferase PC20:35Z,8Z,11Z16:0 Ethanolamine ATP O- Phosphoethanolamine ADP H Cytidine triphosphate PP i CDP- Ethanolamine L-Serine Choline PS20:35Z,8Z,11Z16:0 PS20:35Z,8Z,11Z16:0 PE20:35Z,8Z,11Z16:0 CO 2 DG20:35Z,8Z,11Z16:00:0 Cytidine monophosphate PE20:35Z,8Z,11Z16:0 Phosphatidylcholine Biosynthesis Endoplasmic Reticulum Membrane Mitochondrial Outer Membrane Cytosol Endoplasmic Reticulum Lumen Mitochondrial Intermembrane Spance Mitochondrial Matrix Mitochondrial Inner Membrane 