A Binding Protein for Fatty Acids in Cytosol of Intestinal Mucosa, Liver, Myocardium, and Other Tissues

Abstract

A protein of molecular weight approximately 12,000 which binds long-chain fatty acids and certain other lipids has been identified in cytosol of intestinal mucosa, liver, myocardium, adipose tissue, and kidney. Binding is noncovalent and is greater for unsaturated than for saturated and medium-chain fatty acids. This protein appears to be identical with the smaller of two previously described cytoplasmic anion-binding proteins. Binding of long-chain fatty acids by this protein is greater than that of other anions tested, including sulfobromophthalein, and does not depend on negative charge alone. The presence of this binding protein may explain previously observed differences in intestinal absorption among fatty acids, and the protein may participate in the utilization of long-chain fatty acids by many mammalian tissues.

Effect of fatty acids on plasma membrane lipid dynamics and cation permeability in neuroblastoma cells

“…The possible involvement of ~ cytoplasmic fatty acid binding protein in incorporation might, however, explain the observed differences. The affinity of this protein for fatty acids is in the order stearic << linoleic < oleic acid [46]. As shown in Table I, the unsaturated fatty acids are incorporated mainly into the phospholipid and triacylglycerol fractions, while hardly any free fatty acid was detected in the cells.…”

Two distinct types of fatty acid-binding protein are expressed in heart ventricle of Antarctic teleost fishes

“…Since their first description [1,2], nine types of FABP have been identified in mammals, each of which is the product of a distinct gene and exhibits tissue-specific expression (for reviews see [3,4]). Although the primary sequence of these FABP types may differ considerably, the tertiary structure of the proteins is maintained as a ' clam shell ' comprised of two orthogonal β-sheets connected by two α-helices.…”

Primary structure of rat liver Z‐protein

“…In the cytosol of animal tissues, Z-protein [I] (fatty acid-binding protein [2] or squalene-and sterolcarrier protein [3]) binds free fatty acids, their CoA derivatives, bilirubin, organic anions and other small molecules [4]. It appears to play a significant role as a carrier protein in reversing the inhibitory effect of palmitoyl CoA on acetyl CoA carboxylase [5] and on adenine nucleotide transport of isolated mitochondria [6].…”