A comparison of the molecular specificities of whole cell and endonuclear phosphatidylcholine synthesis.
Deuterated choline-d(9) labelling of IMR-32 cells enabled comparison of the molecular specificities of whole cell and endonuclear phosphatidylcholine synthesis after 96 h polyunsaturated fatty acid supplementation. Surprisingly, while cell phosphatidylcholine synthesis and remodelling reflected a pattern of polyunsaturated fatty acid accretion, the saturated endonuclear phosphatidylcholine pool was only transiently labelled with polyunsaturates. Periodic endonuclear accumulations of the lipid second messenger diacylglycerol, mobilised from unsaturated phosphatidylinositol or saturated phosphatidylcholine, accompany cell proliferation. Non-specific incorporation into endonuclear phosphatidylcholine and selective removal or remodelling of unsaturated molecular species may form part of a single 'off switch' recycling all endonuclear diacylglycerol accumulations.
Hunt
Alan N
AN
Mailpoint 803, Allergy and Inflammation Sciences, Division of Infection, Inflammation and Repair, School of Medicine, University of Southampton, UK. anh@soton.ac.uk
Clark
Graeme T
GT
Neale
James R
JR
Postle
Anthony D
AD
D002467:Cell Nucleus / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage; D006801:Humans; D010713:Phosphatidylcholines / Q000096:biosynthesis*; D014407:Tumor Cells, Cultured
D005231:Fatty Acids, Unsaturated; D010713:Phosphatidylcholines