Biomaterial Database

Role of phosphatidylcholine biosynthesis in the regulation of lipoprotein homeostasis. 2008

Dennis E Vance

Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada. dennis.vance@ualberta.ca

OBJECTIVE This review summarizes the role of phosphatidylcholine metabolism in plasma lipoprotein homeostasis. RESULTS While it was previously known that phosphatidylcholine biosynthesis was required for normal hepatic VLDL secretion, recent studies have shown that both phosphatidylcholine biosynthetic pathways (the cytidine 5'-diphosphocholine and the phosphatidylethanolamine methylation pathways) are required. In addition, a requirement of acyl-coenzyme A synthetase 3, but not acyl-coenzyme A synthetase 1 or 4, for phosphatidylcholine synthesis and VLDL secretion is now documented. ABCA1 has been implicated in the transfer of phosphatidylcholine to apolipoproteinA-1 both during and after secretion of apolipoproteinA-1. Other studies have introduced the concept of reverse phosphatidylcholine transport in which both HDL and LDL supply phosphatidylcholine to the liver. An unexpected finding is that half of the phosphatidylcholine delivered to liver from lipoproteins is converted into triacylglycerol. CONCLUSIONS The liver is both a donor of phosphatidylcholine during the assembly and secretion of lipoproteins as well as a recipient of phosphatidylcholine from plasma lipoproteins.

UI	MeSH Term	Description	Entries
D008075	Lipoproteins, HDL	A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.	High Density Lipoprotein,High-Density Lipoprotein,High-Density Lipoproteins,alpha-Lipoprotein,alpha-Lipoproteins,Heavy Lipoproteins,alpha-1 Lipoprotein,Density Lipoprotein, High,HDL Lipoproteins,High Density Lipoproteins,Lipoprotein, High Density,Lipoprotein, High-Density,Lipoproteins, Heavy,Lipoproteins, High-Density,alpha Lipoprotein,alpha Lipoproteins
D008079	Lipoproteins, VLDL	A class of lipoproteins of very light (0.93-1.006 g/ml) large size (30-80 nm) particles with a core composed mainly of TRIGLYCERIDES and a surface monolayer of PHOSPHOLIPIDS and CHOLESTEROL into which are imbedded the apolipoproteins B, E, and C. VLDL facilitates the transport of endogenously made triglycerides to extrahepatic tissues. As triglycerides and Apo C are removed, VLDL is converted to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LOW-DENSITY LIPOPROTEINS from which cholesterol is delivered to the extrahepatic tissues.	Pre-beta-Lipoprotein,Prebeta-Lipoprotein,Prebeta-Lipoproteins,Very Low Density Lipoprotein,Very-Low-Density Lipoprotein,Very-Low-Density Lipoproteins,Lipoprotein VLDL II,Lipoproteins, VLDL I,Lipoproteins, VLDL III,Lipoproteins, VLDL1,Lipoproteins, VLDL2,Lipoproteins, VLDL3,Pre-beta-Lipoproteins,Lipoprotein, Very-Low-Density,Lipoproteins, Very-Low-Density,Pre beta Lipoprotein,Pre beta Lipoproteins,Prebeta Lipoprotein,Prebeta Lipoproteins,VLDL Lipoproteins,VLDL1 Lipoproteins,VLDL2 Lipoproteins,VLDL3 Lipoproteins,Very Low Density Lipoproteins
D010713	Phosphatidylcholines	Derivatives of PHOSPHATIDIC ACIDS in which the phosphoric acid is bound in ester linkage to a CHOLINE moiety.	Choline Phosphoglycerides,Choline Glycerophospholipids,Phosphatidyl Choline,Phosphatidyl Cholines,Phosphatidylcholine,Choline, Phosphatidyl,Cholines, Phosphatidyl,Glycerophospholipids, Choline,Phosphoglycerides, Choline
D006706	Homeostasis	The processes whereby the internal environment of an organism tends to remain balanced and stable.	Autoregulation
D049294	Phospholipid Transfer Proteins	A ubiquitous family of proteins that transport PHOSPHOLIPIDS such as PHOSPHATIDYLINOSITOL and PHOSPHATIDYLCHOLINE between membranes. They play an important role in phospholipid metabolism during vesicular transport and SIGNAL TRANSDUCTION.	Phosphatidylinositol Transfer Proteins,Aminophospholipid Flippase,Aminophospholipid Transfer Proteins,Aminophospholipid Translocase,Aminophospholipid Translocator,Aminophospholipid Transporter,Lecithin Transfer Protein,Nonspecific Phospholipid Transfer proteins,Phosphatidyl Transfer Protein,Phosphatidylcholine Exchange Protein,Phosphatidylcholine Transfer Protein,Phosphatidylcholine Transfer Proteins,Phosphatidylinositol Exchange Protein,Phosphatidylinositol Transfer Protein,Phosphatidylinositol Transfer Protein alpha,Phosphatidylinositol Transfer Protein beta,Phosphatidylserine Translocase,Phospholipid Exchange Protein,Phospholipid Exchange Proteins,Phospholipid Scramblase,Phospholipid Transfer Protein,Phospholipid Translocating Protein,Scramblase, Phospholipid,Transfer Proteins, Phospholipid,Translocase, Aminophospholipid,Translocase, Phosphatidylserine,Translocator, Aminophospholipid,Transporter, Aminophospholipid
D050918	Phosphatidylethanolamine N-Methyltransferase	An enzyme that catalyses three sequential METHYLATION reactions for conversion of phosphatidylethanolamine to PHOSPHATIDYLCHOLINE.	Cephalin N-Methyltransferase,PHET Methyltransferase II,Phosphatidylethanolamine Methyltransferase,Phosphatidylethanolamine N-Methyltransferase-2,Phosphatidylethanolamine-Methyltransferase II,Phosphatidylethanolamine-Phosphatidylcholine N-Methyltransferase,Phospholipid Methyltransferase II,S-Adenosylmethionine Phosphatidylethanolamine N-Methyltransferase,Cephalin N Methyltransferase,Methyltransferase II, PHET,Methyltransferase II, Phospholipid,Methyltransferase, Phosphatidylethanolamine,N-Methyltransferase, Cephalin,N-Methyltransferase, Phosphatidylethanolamine,N-Methyltransferase, Phosphatidylethanolamine-Phosphatidylcholine,N-Methyltransferase, S-Adenosylmethionine Phosphatidylethanolamine,N-Methyltransferase-2, Phosphatidylethanolamine,Phosphatidylethanolamine Methyltransferase II,Phosphatidylethanolamine N Methyltransferase,Phosphatidylethanolamine N Methyltransferase 2,Phosphatidylethanolamine N-Methyltransferase, S-Adenosylmethionine,Phosphatidylethanolamine Phosphatidylcholine N Methyltransferase,S Adenosylmethionine Phosphatidylethanolamine N Methyltransferase
D019916	Choline-Phosphate Cytidylyltransferase	An enzyme that catalyzes the transfer of cytidylate (CMP) to choline phosphate to form CDPcholine. It is the rate-limiting enzyme in the choline pathway for the biosynthesis of phosphatidylcholine. Its activity is increased by glucocorticoids. EC 2.7.7.15.	CTP Phosphocholine Cytidylyltransferase,CDP-Choline Synthetase,CTP Phosphocholine Cytidylyl-Transferase,CTP Phosphorylcholine Cytidyltransferase,Phosphocholine Cytidyltransferase,Phosphorylcholine Cytidyl Transferase,CDP Choline Synthetase,CTP Phosphocholine Cytidylyl Transferase,Choline Phosphate Cytidylyltransferase,Cytidyl Transferase, Phosphorylcholine,Cytidyltransferase, CTP Phosphorylcholine,Cytidyltransferase, Phosphocholine,Cytidylyl-Transferase, CTP Phosphocholine,Cytidylyltransferase, CTP Phosphocholine,Cytidylyltransferase, Choline-Phosphate,Phosphocholine Cytidylyl-Transferase, CTP,Phosphocholine Cytidylyltransferase, CTP,Phosphorylcholine Cytidyltransferase, CTP,Synthetase, CDP-Choline,Transferase, Phosphorylcholine Cytidyl