The dietary essential fatty acid (EFA) linoleic acid (LA) is activated to a high energy form known as linoleoyl-CoA by the action of long-chain acyl-CoA synthetases (ACSLs). Thioesterification of long-chain fatty acids into their acyl-CoA derivatives is considered to be the first committed step in fatty acid metabolism. Formation of acyl-CoA allows an otherwise non-reactive fatty acid to participate in biosynthetic or catabolic pathways. This acyl CoA form is converted to its longer-chain polyunsaturated products by a series of desaturation and elongation reactions (Ellis et al. 2010, Watkins 2008).