Cellular fatty acid transport in heart and skeletal muscle as facilitated by proteins.
Despite the importance of long-chain fatty acids (FA) as fuels for heart and skeletal muscles, the mechanism of their cellular uptake has not yet been clarified. There is dispute as to whether FA are taken up by the muscle cells via passive diffusion and/or carrier-mediated transport. Kinetic studies of FA uptake by cardiac myocytes and the use of membrane protein-modifying agents have suggested the bulk of FA uptake is due to a protein component. Three membrane-associated FA-binding proteins were proposed to play a role in FA uptake, a 40-kDa plasma membrane FA-binding protein (FABPpm), an 88-kDa FA translocase (FAT/CD36), and a 60-kDa FA transport protein (FATP). In cardiac and skeletal myocytes the intracellular carrier for FA is cytoplasmic heart-type FA-binding protein (H-FABP), which likely transports FA from the sarcolemma to their intracellular sites of metabolism. A scenario is discussed in which FABPpm, FAT/CD36, and H-FABP, probably assisted by an albumin-binding protein, cooperate in the translocation of FA across the sarcolemma.
Department of Kinesiology, University of Waterloo, Ontario, Canada.
J J
JJ
Luiken
F G
FG
Schaap
F A
FA
van Nieuwenhoven
G J
GJ
van der Vusse
A
A
Bonen
J F
JF
Glatz
D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids / Q000378:metabolism*; D006801:Humans; D008954:Models, Biological; D018482:Muscle, Skeletal / Q000378:metabolism*; D018996:Myelin P2 Protein / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D009363:Neoplasm Proteins; D012508:Sarcolemma / Q000378:metabolism; D025521:Tumor Suppressor Proteins
D002352:Carrier Proteins; C107608:FABP7 protein, human; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D018996:Myelin P2 Protein; D009363:Neoplasm Proteins; D025521:Tumor Suppressor Proteins