Figure 2. Lipid metabolic pathways across different cellular compartments.

Fatty acids can either be taken up by the cell, through transporters including CD36 or the FATP family, or synthesized de novo from glucose via conversion to acetyl-CoA. Acetyl-CoA can be used for cholesterol synthesis via the mevalonate pathway or for the production or extension of new fatty acids. The ACSL enzymes ligate coenzyme A to fatty acids for elongation, beta oxidation, ether lipid synthesis, triglyceride synthesis, or phospholipid synthesis. Phospholipids are transported to the membrane, where they can then be remodeled by the Lands’ cycle.

ACAT, acetyl-CoA acetyltransferase; HMGCS, hydroxymethylglutaryl-CoA synthase; HMGCR, hydroxymethylglutaryl-CoA reductase; SQLE, squalene monooxygenase; 7-DHC, 7-dehydrocholesterol; DHCR7, 7-dehydrocholesterol reductase; LDLR, low density lipoprotein receptor; CD36, fatty acid translocase; FATP, fatty acid transport protein; ACLY, ATP-citrate lyase; ACC, acetyl-CoA carboxylase; FASN, fatty acid synthase; PA, palmitic acid; SA, stearic acid; OA, oleic acid; LA, linoleic acid; AA, arachidonic acid; ACSL, acyl-CoA synthetase, long chain; ELOVL, elongation of very long chain fatty acid protein; SCD, stearoyl-CoA desaturase; FADS, fatty acid desaturase; CPT1, carnitine palmitoyltransferase 1; CACT, carnitine-acylcarnitine translocase; ACAD, acyl-CoA dehydrogenase; DECR1, 2,4-dienoyl-CoA reductase 1; ECH, enoyl-CoA hydratase; HADH, hydroxyacyl-CoA dehydrogenase; PISD, phosphatidylserine decarboxylase proenzyme; GPAT, glycerol-3-phosphate acyltransferase; AGPAT, acylglycerol-3-phosphate O-acyltransferase; DGAT, diacylglycerol acyltransferase; C/EPT, choline/ethanolamine phosphotransferase; PE, phosphatidylethanolamine, PC, phosphatidylcholine; PSS, phosphatidylserine synthase; PEDS1, plasmanylethanolamine desaturase 1; FAR1, fatty acyl-CoA reductase 1; GNPAT, glyceronephosphate O-acyltransferase; DHAP, dihydroxyacetone phosphate; AGPS, alkylglycerone phosphate synthase.