title: Fatty acid transport and transporters in muscle are critically regulated by Akt2.
abstract: Muscle contains various fatty acid transporters (CD36, FABPpm, FATP1, FATP4). Physiological stimuli (insulin, contraction) induce the translocation of all four transporters to the sarcolemma to enhance fatty acid uptake similarly to glucose uptake stimulation via glucose transporter-4 (GLUT4) translocation. Akt2 mediates insulin-induced, but not contraction-induced, GLUT4 translocation, but its role in muscle fatty acid transporter translocation is unknown. In muscle from Akt2-knockout mice, we observed that Akt2 is critically involved in both insulin-induced and contraction-induced fatty acid transport and translocation of fatty acid translocase/CD36 (CD36) and FATP1, but not of translocation of fatty acid-binding protein (FABPpm) and FATP4. Instead, Akt2 mediates intracellular retention of both latter transporters. Collectively, our observations reveal novel complexities in signaling mechanisms regulating the translocation of fatty acid transporters in muscle.
authors: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Swati S
authors: SS
authors: Jain
authors: Department of Molecular Genetics, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, P.O. Box 616, Maastricht NL-6200 MD, The Netherlands. Electronic address: j.luiken@maastrichtuniversity.nl.
authors: Joost J F P
authors: JJ
authors: Luiken
authors: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Laelie A
authors: LA
authors: Snook
authors: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Xiao Xia
authors: XX
authors: Han
authors: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Graham P
authors: GP
authors: Holloway
authors: Department of Molecular Genetics, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, P.O. Box 616, Maastricht NL-6200 MD, The Netherlands.
authors: Jan F C
authors: JF
authors: Glatz
authors: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors: Arend
authors: A
authors: Bonen
mesh_terms: D000818:Animals; D050612:Fatty Acid Transport Proteins / Q000378:metabolism*; D050556:Fatty Acid-Binding Proteins / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D055786:Gene Knockout Techniques; D005947:Glucose / Q000378:metabolism; D051275:Glucose Transporter Type 4 / Q000378:metabolism; D007328:Insulin / Q000378:metabolism; D051379:Mice; D009132:Muscles / Q000166:cytology / Q000378:metabolism*; D010641:Phenotype; D010766:Phosphorylation; D021381:Protein Transport; D051057:Proto-Oncogene Proteins c-akt / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D050612:Fatty Acid Transport Proteins; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D051275:Glucose Transporter Type 4; D007328:Insulin; C494922:Akt2 protein, mouse; D051057:Proto-Oncogene Proteins c-akt; D005947:Glucose
keywords: Akt2; Contraction; Fatty acid translocase/CD36; Fatty acid transport; Glucose transporter-4