INTESTINAL AND LIVER FATTY-ACID-BINDING PROTEINS DIFFERENTIALLY AFFECT FATTY-ACID UPTAKE AND ESTERIFICATION IN L-CELLS

Differential effects of intestinal (I-FABP) or liver (L-FABP) fatty ac id binding proteins on fatty acid uptake and esterification were exami ned using transfected mouse L-cell fibroblasts. L-FABP, but not I-FABP , expression increased the initial rate and extent of cis-parinaric ac id uptake by 50 and 29%, respectively, compared to control cells. I-FA BP and L-FABP expression preferentially increased [H-3]-oleic acid inc orporation into triacylglycerols by 5.5-fold and 3.8-fold, respectivel y. While both L-FABP and I-FABP increased esterification of [H-3]-olei c acid into ethanolamine glycerophospholipids, these proteins had oppo site effect on esterification into choline glycerophospholipids. These data show for the first time that distinct FABP differentially affect both fatty acid uptake and intracellular esterification.