Control of fatty acid synthesis

Figure 8-1. Hormonal regulation of fat metabolism. A Control of fatty acid synthesis by reversible phosphorylation of acetyl CoA carboxylase. B Regulation of tri-acylglycerol degradation by reversible phosphorylation of hormone-sensitive lipase. cAMP, cyclic adenosine monophosphate HS, hormone-sensitive.

Control of Fatty Acid Synthesis and Oxidation Transport of Fatty Acids into the Mitochondria Sources of Carnitine Long-Chain versus Medium-Chain Fatty Acids The Krebs Cycle... 

Control of fatty-acid synthesis. A schematic of the control of fatty-acid synthesis is presented with the major control steps shown in purple with effectors (both positive and... 

Acetyl-CoA carboxylase and control of fatty acid synthesis. 104... 

See also Acetyl-CoA, Fats, Albumin, Fatty Acid Activation, Oxidation of Saturated Fatty Acids, Oxidation of Unsaturated Fatty Acids, Fatty Acid Biosynthesis Strategy, Palmitate Synthesis from Acetyl-CoA, Fatty Acid Desaturation, Essential Fatty Acids, Control of Fatty Acid Synthesis, Molecular Structures and Properties of Lipids (from Chapter 10)... 

See also Fatty Acid biosynthesis. Control of Fatty Acid Synthesis, Maintaining Blood Glucose levels... 

See also Action of Insulin (from Chapter 23), Gluconeogenesis, Control of Fatty Acid Synthesis, Hormonal Regulation of Fuel Metabolism, Figure 5.21, Table 23.2... 

Discuss the different modes of regulation of acetyl CoA carboxylase. Explain the reciprocal control of fatty acid synthesis and degradation through global and local regulation and dietary composition. 

Tricarboxylic Acid Cycle Intermediates and the Control of Fatty Acid Synthesis and Ketogenesis... 

Control of fatty acid synthesis is exerted at the level of acetyl-CoA carboxylase and fatty acid synthetase, as well as on the supporting pathways which provide immediate carbon precursors and reducing equivalents. The known and potential control sites in the overall biosynthetic process are illustrated in Fig. 2 and enumerated below. 

Harwood J L, Stumpf P K 1971 Fat metabolism in higher plants. XLIII. Control of fatty acid synthesis in germinating seeds. Arch Biochem Biophys 142 281-291... 

Medium chain fatty acids (C,-Ci4) are unusual fetty adds found in the seed oils of several plant species such as Cuphea and California bay [1]. Medium chain fetty acids are produced by premature chain termination of fetty acid synthesis, mediated by a medium chain acyl-ACP thioesterase (MCTE) [2,3]. Since medium chain fetty acids are a valuable renewable resource, one goal of researchers has been to develop a medium chain-producing annual crop plant using genetic transformation [4]. Workers at Calgene transformed Brassica napus with California bay medium chain acyl-ACP thioesterase cDNA, testing the ability of a seed specific napin promote or the constitutive CaMV 35S promoter to alter seed oil fatty acid composition. We have used these transformants to evaluate possible roles for acyl-ACP chain length termination in the control of fatty acid synthesis. 

It is the author s conviction that the critical questions regarding the atherosclerosis problem are What is the regulator of lipogenesis within vascular tissues and how do atherogenic stimuli perturb this regulator Decisive answers to these questions will be the most likely source from which we will be able to draw information with potential preventive and therapeutic value. Unfortunately, at present very little is known about the control of fatty acid synthesis in arterial tissue. 

Attention has been directed also at fatty acid synthetase as a control site for the regulation of fatty acid synthesis. This multienzyme complex mediates the synthesis of saturated fatty acids from malonyl-CoA in a reaction requiring acetyl-CoA and NADPH. Details of the enzyme complex and reaction sequence have been reviewed recently (Volpe and Vagelos, 1976 Katiyar and Porter, 1977 Block and Vance, 1977). All available data suggest that while modulation of acetyl-CoA carboxylase activity represents the essential site of short-term control of fatty acid synthesis, long-term control of fatty acid synthesis may rest with the rate of de novo synthesis of the fatty acid synthetase complex. 

The control of fatty acid synthesis can take place at a number of enzyme steps... 

Figure 4.14). Once inside, they are esterified into acylglycerols. In discussing the control of acylglycerol synthesis, we shall be discussing the esterification of fatty acids synthesized de novo or released from circulating lipoproteins. The control of fatty acid synthesis itself is discussed in section 3.2.7. 

---