title: Fatty acid binding proteins have the potential to channel dietary fatty acids into enterocyte nuclei.
abstract: Intracellular lipid binding proteins, including fatty acid binding proteins (FABPs) 1 and 2, are highly expressed in tissues involved in the active lipid metabolism. A zebrafish model was used to demonstrate differential expression levels of fabp1b.1, fabp1b.2, and fabp2 transcripts in liver, anterior intestine, and brain. Transcription levels of fabp1b.1 and fabp2 in the anterior intestine were upregulated after feeding and modulated according to diet formulation. Immunofluorescence and electron microscopy immunodetection with gold particles localized these FABPs in the microvilli, cytosol, and nuclei of most enterocytes in the anterior intestinal mucosa. Nuclear localization was mostly in the interchromatin space outside the condensed chromatin clusters. Native PAGE binding assay of BODIPY-FL-labeled FAs demonstrated binding of BODIPY-FLC(12) but not BODIPY-FLC(5) to recombinant Fabp1b.1 and Fabp2. The binding of BODIPY-FLC(12) to Fabp1b.1 was fully displaced by oleic acid. In vivo experiments demonstrated, for the first time, that intestinal absorption of dietary BODIPY-FLC(12) was followed by colocalization of the labeled FA with Fabp1b and Fabp2 in the nuclei. These data suggest that dietary FAs complexed with FABPs are able to reach the enterocyte nucleus with the potential to modulate nuclear activity.
authors.affiliation: Facultad de Ciencias, Universidad de la República, 11400 Montevideo, Uruguay.
authors.forename: Adriana
authors.initials: A
authors.lastname: Esteves
authors.affiliation: University Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), F-33615 Pessac, France INSERM, U1211, F-33076, Bordeaux, France.
authors.forename: Anja
authors.initials: A
authors.lastname: Knoll-Gellida
authors.affiliation: Facultad de Ciencias, Universidad de la República, 11400 Montevideo, Uruguay.
authors.forename: Lucia
authors.initials: L
authors.lastname: Canclini
authors.affiliation: Facultad de Ciencias, Universidad de la República, 11400 Montevideo, Uruguay.
authors.forename: Maria Cecilia
authors.initials: MC
authors.lastname: Silvarrey
authors.affiliation: University Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), F-33615 Pessac, France INSERM, U1211, F-33076, Bordeaux, France.
authors.forename: Michèle
authors.initials: M
authors.lastname: André
authors.affiliation: University Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), F-33615 Pessac, France INSERM, U1211, F-33076, Bordeaux, France p.babin@gpp.u-bordeaux1.fr.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Babin
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D020895:Enterocytes / Q000378:metabolism; D050556:Fatty Acid-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D050356:Lipid Metabolism / Q000235:genetics; D015027:Zebrafish / Q000235:genetics* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C497193:FABP2 protein, zebrafish; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D029961:Zebrafish Proteins; C513421:fatty acid-binding protein 1b, zebrafish
keywords: BODIPY-labeled fatty acids; Danio rerio; diet and dietary lipids; electron microscopy; fatty acid binding protein 1; fatty acid binding protein 2; fluorescence microscopy; gene expression; intestine; nucleus; zebrafish