Fatty acid-binding protein

About: Fatty acid-binding protein is a research topic. Over the lifetime, 1721 publications have been published within this topic receiving 81530 citations. The topic is also known as: FABP.

Characterization of critical factors influencing gene expression of two types of fatty acid-binding proteins (L-FABP and Lb-FABP) in the liver of birds.

Abstract: In avian species, two types of intracellular lipid-binding proteins are abundant in the liver, the liver fatty acid-binding protein (L-FABP) and the liver basic fatty acid-binding protein (Lb-FABP). Both FABPs are capable of forming complexes with free fatty acids and bile acids, but the functional distinction between L-FABP and Lb-FABP in avian liver is not fully understood. To gain insights into the functional distinction between L-FABP and Lb-FABP, we investigated the expression of both genes in relation to the pre- and post-hatching development, diurnal cycle and feeding state in the livers of chicken (Gallus gallus) and Japanese quail (Coturnix japonica). In chickens, the Lb-FABP mRNA was expressed only in the liver, while the L-FABP was expressed in both liver and intestinal tissues. Only small amounts of the L-FABP and Lb-FABP mRNAs were detected in the liver during chicken embryogenesis, but at the onset of hatching a dramatic increase in mRNA expression was observed for both genes, suggesting that the expression of the L-FABP and Lb-FABP genes is synchronized at developmental stages. Remarkably, the diurnal expression pattern differed between the two genes under a 16L:8D condition in sexually mature quail: L-FABP gene expression transiently increased at the end of the light cycle, whereas Lb-FABP gene expression peaked during the early part of the light cycle and gradually decreased as the dark period approached. We attempted to identify the factors regulating the diurnal gene expression pattern, and found that feeding stimulation was a critical factor inducing Lb-FABP gene expression irrespective of light condition. On the other hand, feeding stimulation only slightly stimulated expression of the L-FABP gene, and was not always its primary determinant. These results suggest that L-FABP and Lb-FABP play different roles in metabolic process during the postprandial state.

Ascaridia galli fatty acid-binding protein, a member of the nematode polyprotein allergens family.

Abstract: A fatty acid-binding protein from the nematode Ascaridia galli was characterized. The gene was isolated and recombinantly expressed in Escherichia coli. According to the deduced amino acid sequence A. galli fatty acid-binding protein (AgFABP) belongs to the family of nematode polyprotein allergens, as shown by Western blotting and PCR analysis with genomic DNA and cDNA. Both native and recombinant proteins bind fatty acids and retinoids with high affinity. The fluorescent fatty acid analogue 11-[(5-dimethylaminonaphthalene-1-sulfonyl)amino] undecanoic acid (DAUDA) shows substantial changes in its emission spectrum when bound to AgFABP; this binding is reversed by fatty acids such as oleate. Moreover, changes of the intrinsic fluorescence of retinol and retinoic acid confirm retinoid binding activity of AgFABP. Fluorescence titration experiments with DAUDA indicate stoichiometric binding to a single binding site per monomer unit with affinities (Kd) of 1.6 and 1.8 x 10(-7) m for native and the recombinant protein, respectively. The apparent binding affinities of the nonfluorescent ligands were calculated in displacement experiments with DAUDA and values in the same range were obtained for myristic, palmitic, oleic, linoleic, arachidonic and retinoic acid. Additionally, the binding affinity of AgFABP for oleate and palmitate was determined by direct and indirect radiochemical analysis and the values obtained were similar to those from the fluorescent experiments. Both proteins show a preference for the binding of long-chain saturated and unsaturated fatty acids, but not for short chain (C3-C12) and branched fatty acids, cholesterol and tryptophan.

Nomenclature of fatty acid-binding proteins.

Abstract: A variety of designations is currently being used to refer to cellular fatty acid-binding proteins (FABPs). Besides from the use of other general names (e.g. Z protein), confusion mostly arises from the application of various abbreviations and symbols to denote the tissue(s) of origin and cellular localization (cytoplasm, plasma membrane) of a specific FABP. In order to minimize confusion a more unified and rational nomenclature is proposed, which is based on application of the formula X-FABPY. The prefix X is a capital letter indicating the tissue of greatest abundance, the suffix Y similarly denotes the (sub)cellular localization of the protein. The general and functional name ‘fatty acid-binding protein’ (FABP) is preferred for the cellular proteins with the property to bind fatty acids, unless future research reveals that the binding of fatty acids is not the primary biological property or physiological role of (some of) these proteins

Cloning and sequencing of complementary DNA for fatty acid binding protein from rainbow trout heart.

Abstract: A cDNA encoding a rainbow trout homologue of mammalian heart fatty acid binding protein (H-FABP) was isolated. The deduced protein sequence is 75% identical to that of rat H-FABP. The structural conservation of H-FABPs and their evolutionary relationship are discussed.