Uptake of fatty acids by jejunal mucosal cells is mediated by a fatty acid binding membrane protein.

Bovine liver was shown to contain a hitherto undescribed medium-chain acyl-CoA-binding protein. The protein co-purifies with fatty-acid-binding proteins, but was, unlike these proteins, unable to bind fatty acids. The protein induced synthesis of medium-chain acyl-CoA esters on incubation with goat mammary-gland fatty acid synthetase. The possible function of the protein is discussed.

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A sensitive immunoassay for rat fatty acid translocase (CD36) using phage antibodies selected on cell transfectants: abundant presence of fatty acid translocase/CD36 in cardiac and red skeletal muscle and up-regulation in diabetes

Biochemical Journal ◽

10.1042/bj3370407 ◽

1999 ◽

Vol 337 (3) ◽

pp. 407-414 ◽

Cited By ~ 22

Author(s):

Maurice M. A. L. PELSERS ◽

Jan T. LUTGERINK ◽

Frans A. van NIEUWENHOVEN ◽

Narendra N. TANDON ◽

Ger J. van der VUSSE ◽

...

Keyword(s):

Fatty Acid ◽

Membrane Protein ◽

Diabetic Rats ◽

Direct Selection ◽

Antibody Library ◽

Fatty Acid Binding ◽

Fatty Acid Translocase ◽

Phage Antibody ◽

Phage Antibodies ◽

Set Up

The rat membrane protein fatty acid translocase (FAT), which shows sequence similarity to human CD36 (a membrane protein supposedly involved in a variety of membrane processes), is implicated in the transport of long-chain fatty acids across cellular membranes. To set up an immunoassay for quantification of FAT in different tissues, we isolated a series of anti-FAT antibodies by panning a large naive phage antibody library on FAT-transfected H9c2 cells. All seven different phage antibody fragments isolated reacted specifically with FAT, and most likely recognize the same or closely located immunodominant sites on FAT, as a competitive monoclonal antibody (mAb) (CLB-IV7) completely blocked the binding of all these phage antibodies to cells. A sandwich ELISA was set up using mAb 131.4 (directed against purified CD36 from human platelets) as capture antibody and phage antibodies and anti-phage sera as detector. With this ELISA (sensitivity 0.05 µg/ml), the FAT content in isolated cardiomyocytes was found to be comparable with that of total heart (≈ 3 mg/g of protein), while liver tissue and endothelial cells were below the detection limit (< 0.1 mg of FAT/g of protein). During rat heart development, protein levels of FAT rose from 1.7±0.7 mg/g of protein on the day before birth to 3.6±0.4 mg/g of protein on day 70. Comparing control with streptozotocin-induced diabetic rats, a statistically significant (P< 0.05) 2–4-fold increase of FAT was seen in heart (from 4.2±2.3 to 11.0±5.7 mg/g of protein), soleus (from 0.6±0.1 to 1.4±0.5 mg/g of protein) and extensor digitorum longus (EDL) muscle (from 0.3±0.1 to 1.2±0.8 mg/g of protein). In addition, the FAT contents of each of these muscles were found to be of similar magnitude to the contents of cytoplasmic heart-type fatty-acid-binding protein in both diabetic rats and controls, supporting the suggested roles of these two proteins in cellular fatty acid metabolism. This is the first time phage display technology has been succesfully applied for direct selection, from a large naive antibody library, of antibodies that recognize selected membrane proteins in their natural context.

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Up-regulation of the expression of the gene for liver fatty acid-binding protein by long-chain fatty acids

Biochemical Journal ◽

10.1042/bj3190483 ◽

1996 ◽

Vol 319 (2) ◽

pp. 483-487 ◽

Cited By ~ 47

Author(s):

Claire MEUNIER-DURMORT ◽

Hélène POIRIER ◽

Isabelle NIOT ◽

Claude FOREST ◽

Philippe BESNARD

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Binding Protein ◽

Fold Increase ◽

Long Chain Fatty Acids ◽

Liver Fatty Acid ◽

Fatty Acid Binding ◽

Acid Binding Protein ◽

Fabp Gene ◽

Long Chain

The role of fatty acids in the expression of the gene for liver fatty acid-binding protein (L-FABP) was investigated in the well-differentiated FAO rat hepatoma cell line. Cells were maintained in serum-free medium containing 40 µM BSA/320 µM oleate. Western blot analysis showed that oleate triggered an approx. 4-fold increase in the cytosolic L-FABP level in 16 h. Oleate specifically stimulated L-FABP mRNA in time-dependent and dose-dependent manners with a maximum 7-fold increase at 16 h in FAO cells. Preincubation of FAO cells with cycloheximide prevented the oleate-mediated induction of L-FABP mRNA, showing that protein synthesis was required for the action of fatty acids. Run-on transcription assays demonstrated that the control of L-FABP gene expression by oleate was, at least in part, transcriptional. Palmitic acid, oleic acid, linoleic acid, linolenic acid and arachidonic acid were similarly potent whereas octanoic acid was inefficient. This regulation was also found in normal hepatocytes. Therefore long-chain fatty acids are strong inducers of L-FABP gene expression. FAO cells constitute a useful tool for studying the underlying mechanism of fatty acid action.

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The integrity of the α-helical domain of intestinal fatty acid binding protein is essential for the collision-mediated transfer of fatty acids to phospholipid membranes

Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids ◽

10.1016/j.bbalip.2008.01.005 ◽

2008 ◽

Vol 1781 (4) ◽

pp. 192-199 ◽

Cited By ~ 15

Author(s):

G.R. Franchini ◽

J. Storch ◽

B. Corsico

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Binding Protein ◽

Binding Protein ◽

Phospholipid Membranes ◽

Fatty Acid Binding ◽

Acid Binding Protein ◽

Helical Domain

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Conditions for oxygen and substrate transport in muscles in exercising mammals

Journal of Experimental Biology ◽

10.1242/jeb.160.1.263 ◽

1991 ◽

Vol 160 (1) ◽

pp. 263-283 ◽

Cited By ~ 4

Author(s):

H. Hoppeler ◽

R. Billeter

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Work Conditions ◽

High Energy ◽

Fatty Acid Transport ◽

Facilitated Diffusion ◽

High Energy Phosphates ◽

Lactate Shuttle ◽

Fatty Acid Binding ◽

Intracellular Location

The structural conditions relevant for metabolite exchange in anaerobic and aerobic work conditions in muscle tissue are reviewed. High-intensity non-steady-state exercise is supported by the phosphocreatine pool, which serves as a shuttle for high-energy phosphates produced by glycolysis and by aerobic metabolism. This is achieved through the intermediary of a topologically organized creatine kinase isozyme system. The muscle capillary network supplies substrate and environmental oxygen to the mitochondria. The network is quantitatively matched to the muscle oxidative capacity, determined structurally by mitochondrial volume. Capillary hematocrit, erythrocyte spacing and oxygen saturation of myoglobin are critical variables for oxygen release from microvessels. Myoglobin greatly helps intracellular oxygen transfer as, under aerobic work conditions, it keeps intracellular oxygen tension low and uniform in the muscle fibers. During sustained submaximal work, muscle cells are fueled by both endogenous (triglycerides and glycogen) and circulatory (lactate, glucose and fatty acids) substrates. A lactate shuttle in which lactate may move through the circulation, as well as directly from fiber to fiber, provides many of the carbohydrate-derived carbon skeletons for terminal oxidation. Glucose is taken up from the interstitial space by facilitated diffusion, mostly mediated by a glucose transporter (GLUT4) that is translocated from an intracellular location to the sarcolemma by activity and insulin. Extramyocellular transport of fatty acids is mediated by albumin, while fatty-acid-binding proteins are held responsible for intracellular fatty acid transport.

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