Cellular uptake of long chain free fatty acids: the structure and function of plasma membrane fatty acid binding protein

2003 ◽  
pp. 47-80 ◽  
Author(s):  
Michael W Bradbury ◽  
Paul D Berk
Keyword(s):  
Fatty Acids ◽  
Plasma Membrane ◽  
Fatty Acid ◽  
Cellular Uptake ◽  
Structure And Function ◽  
Membrane Fatty Acid ◽  
Fatty Acid Binding ◽  
Acid Binding Protein ◽  
And Function ◽  
Long Chain

scholarly journals Constitutive expression of a saturable transport system for non-esterified fatty acids in Xenopus laevis oocytes

1994 ◽  
Vol 297 (2) ◽  
pp. 315-319 ◽  
Author(s):  
S L Zhou ◽  
D Stump ◽  
L Isola ◽  
P D Berk
Keyword(s):  
Fatty Acids ◽  
Plasma Membrane ◽  
Fatty Acid ◽  
Fatty Acid Binding Protein ◽  
Xenopus Laevis Oocytes ◽  
Long Chain Fatty Acids ◽  
Membrane Fatty Acid ◽  
Fatty Acid Binding ◽  
Acid Binding Protein ◽  
Long Chain

In the presence of 150 microM BSA, uptake of [3H]oleate by Xenopus laevis oocytes was a saturable function of the unbound oleate concentration (Vmax. 110 +/- 4 pmol/h per oocyte; Km 193 +/- 11 nM unbound oleate). Oleate uptake was three orders of magnitude faster than that of another test substance, [35S]bromosulphophthalein, and was competitively inhibited by 55 nM unbound palmitate (Vmax. 111 +/- 14 pmol/h per oocyte; Km 424 +/- 63 nM unbound oleate) (P < 0.01). Oleate uptake was also inhibited by antibodies to a 43 kDa rat liver plasma-membrane fatty acid-binding protein, a putative transporter of long-chain fatty acids in mammalian cells; uptake of the medium-chain fatty acid [14C]octanoate was unaffected. Immunofluorescence and immunoblotting demonstrated that the antiserum reacted with a single 43 kDa protein on the oocyte surface. Hence a protein related to the mammalian plasma-membrane fatty acid-binding protein may play a role in saturable uptake of long-chain fatty acids by Xenopus oocytes.

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

1996 ◽  
Vol 319 (2) ◽  
pp. 483-487 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document