Localization of a portion of the liver isoform of fatty-acid-binding protein (L-FABP) to peroxisomes

摘要: The liver isoform of fatty-acid-binding protein (L-FABP) facilitates the cellular uptake, transport and metabolism fatty acids is also involved in regulation gene expressions cell differentiation. Consistent with these functions, L-FABP predominantly present cytoplasm to a lesser extent nucleus; however, significant portion this has been detected fractions containing different organelles. More recent observations, notably on L-FABP-deficient mice, indicated possible direct involvement peroxisomal oxidation long-chain acids. In order clarify links between lipid metabolism, we reinvestigated subcellular distribution protein. Analytical fractionation by method preserving intactness isolated peroxisomes, two-dimensional gel electrophoresis matrix proteins combined MS analysis, immunoelectron microscopy sections demonstrate presence peroxisomes as soluble Peroxisomal was highly inducible clofibrate. induction accompanied marked increase binding capacity for oleic acid cis-parinaric acid. β-oxidation palmitoyl-CoA acyl-CoA thioesterase activity were stimulated L-FABP, indicating that modulates function lipid-metabolizing enzymes. role intraperoxisomal discussed.