title: FIP2 and Rip11 specify Rab11a-mediated cellular distribution of GLUT4 and FAT/CD36 in H9c2-hIR cells.
abstract: Rab11a has been shown to be involved in different vesicle trafficking processes. To further define the functional role of Rab11a in vesicle movement we knocked down gene expression of Rab11a and two of its effectors, Rip11 and FIP2, in H9c2-hIR cells and measured the cell surface abundance of GLUT4myc and FAT/CD36. We observed that by knocking down Rab11a, both GLUT4myc and FAT/CD36 abundance at the plasma membrane were substantially increased. In the case of GLUT4myc, the in vitro knockdown of FIP2 also increased the cell surface abundance of GLUT4myc. Knockdown of both FIP2 and Rip11 increase the abundance of FAT/CD36 at the plasma membrane. Stimulated translocation of GLUT4myc and FAT/CD36 is not altered after gene knockdown of Rab11a. These data therefore show that (i) Rab11a regulates cell surface abundance of both GLUT4 and FAT/CD36 and that (ii) both Rab11a-dependent processes are differently regulated by Rab11a effector proteins.
authors.affiliation: Institute of Clinical Biochemistry and Pathobiochemistry, German Diabetes Center, Auf'm Hennekamp 65, D-40225 Düsseldorf, Germany.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Schwenk
authors.forename: Joost J F P
authors.initials: JJ
authors.lastname: Luiken
authors.forename: Jürgen
authors.initials: J
authors.lastname: Eckel
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D018955:CD36 Antigens / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D018797:Cell Cycle Proteins; D002460:Cell Line; D051275:Glucose Transporter Type 4 / Q000378:metabolism*; D006801:Humans; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins / Q000378:metabolism*; D032383:Myocytes, Cardiac / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology*; D013347:Subcellular Fractions / Q000378:metabolism; D035582:Transcription Factor TFIIIA / Q000378:metabolism*; D020691:rab GTP-Binding Proteins / Q000378:metabolism*; D000099193:rab11 GTP-Binding Proteins
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D018955:CD36 Antigens; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D051275:Glucose Transporter Type 4; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D035582:Transcription Factor TFIIIA; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins; C409460:OPTN protein, human; C485422:RAB11FIP5 protein, human; C495692:SLC2A4 protein, human