title: Fatty acid binding protein, a major protein in the flight muscle of migrating western sandpipers.
abstract: Migratory flight in birds is fueled primarily by fatty acid oxidation imposing a requirement for high rates of fatty acid: (a) transport; (b) uptake; and (c) delivery to intracellular sites of beta-oxidation. Muscle fatty acid binding protein (M-FABP) is a cytosolic protein involved in the intracellular transport of fatty acids. Its expression appears to be correlated with muscle fatty acid oxidation capacity. The M-FABP was isolated for the first time from a long distance migrant bird using: (i) size exclusion; (ii) anion exchange; and (iii) hydroxyapatite chromatography. M-FABP has a molecular weight of approximately 14,000 Da and an isoelectric point of pH 4.8. A partial amino acid sequence of the protein demonstrated homology to M-FABPs from other species (80% identical to human heart FABP). It was estimated that M-FABP comprises approximately 14 and 21% of total cytosolic protein of the pectoralis and heart, respectively; the highest values yet reported from any vertebrate muscle. The abundance of M-FABP in these tissues suggests that the protein may play a key role in fatty acid supply during endurance flight. Thus, it is proposed that a seasonal increase in M-FABP expression could be a component of physiological preparation for migration.
authors.affiliation: Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada. cgugliel@sfu.ca
authors.forename: C G
authors.initials: CG
authors.lastname: Guglielmo
authors.forename: N H
authors.initials: NH
authors.lastname: Haunerland
authors.forename: T D
authors.initials: TD
authors.lastname: Williams
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001717:Birds; D002352:Carrier Proteins / Q000737:chemistry* / Q000302:isolation & purification*; D002645:Chickens; D002845:Chromatography; D002850:Chromatography, Gel; D003600:Cytosol / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005426:Flight, Animal; D006110:Grasshoppers; D006801:Humans; D008969:Molecular Sequence Data; D008970:Molecular Weight; D018482:Muscle, Skeletal / Q000737:chemistry*; D018996:Myelin P2 Protein / Q000737:chemistry* / Q000302:isolation & purification*; D009206:Myocardium / Q000737:chemistry; D009363:Neoplasm Proteins; D012160:Retina / Q000737:chemistry; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014337:Trout; D025521:Tumor Suppressor Proteins
chemical_list: D002352:Carrier Proteins; C107608:FABP7 protein, human; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D018996:Myelin P2 Protein; D009363:Neoplasm Proteins; D025521:Tumor Suppressor Proteins