Stearoyl-CoA Desaturase 1 Deficiency Increases CTP:Choline Cytidylyltransferase Translocation into the Membrane and Enhances Phosphatidylcholine Synthesis in Liver

摘要: Stearoyl-CoA desaturase (SCD) is the rate-limiting enzyme in monounsaturated fatty acid synthesis. Previously, we showed that Scd1 deficiency reduces liver triglyceride accumulation and considerably decreases synthesis of very low density lipoprotein its secretion both lean obese mice. In present study, found significantly modulates hepatic glycerophospholipid profile. The content phosphatidylcholine (PC) was increased by 40% activities CTP:choline cytidylyltransferase (CCT), de novo PC synthesis, choline phosphotransferase were 64 53%, respectively, Scd1-/- contrast, protein level phosphatidylethanolamine N-methyltransferase, an involved via methylation phosphatidylethanolamine, decreased 80% Membrane translocation CCT required for activation. Immunoblot analyses demonstrated twice as much CCTalpha associated with plasma membrane livers compared wild type mice, suggesting mutation leads to increase affinity. incorporation [(3)H]glycerol into 2.5-fold primary hepatocytes those Furthermore, mitochondrial glycerol-3-phosphate acyltransferase activity reduced 42% mice; however, microsomal acyltransferase, diacylglycerol ethanolamine not affected mutation. Our study revealed SCD1 specifically increases promoting enhances biosynthesis liver.