title: Vimentin binds IRAP and is involved in GLUT4 vesicle trafficking.
abstract: Insulin-responsive aminopeptidase (IRAP) and GLUT4 are two major cargo proteins of GLUT4 storage vesicles (GSVs) that are translocated from a postendosomal storage compartment to the plasma membrane (PM) in response to insulin. The cytoplasmic region of IRAP is reportedly involved in retention of GSVs. In this study, vimentin was identified using the cytoplasmic domain of IRAP as bait. The validity of this interaction was confirmed by pull-down assays and immunoprecipitation in 3T3-L1 adipocytes. In addition, it was shown that GLUT4 translocation to the PM by insulin was decreased in vimentin-depleted adipocytes, presumably due to dispersing GSVs away from the cytoskeleton. These findings suggest that the IRAP binding protein, vimentin, plays an important role in retention of GSVs.
authors.affiliation: Department of Nutrition and Metabolism, Institute of Health Biosciences, Tokushima University, Tokushima, Japan.
authors.forename: Yohko
authors.initials: Y
authors.lastname: Hirata
authors.forename: Toshio
authors.initials: T
authors.lastname: Hosaka
authors.forename: Takeo
authors.initials: T
authors.lastname: Iwata
authors.forename: Chung T K
authors.initials: CT
authors.lastname: Le
authors.forename: Bayasgalan
authors.initials: B
authors.lastname: Jambaldorj
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Teshigawara
authors.forename: Nagakatsu
authors.initials: N
authors.lastname: Harada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sakaue
authors.forename: Tohru
authors.initials: T
authors.lastname: Sakai
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Yoshimoto
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Nakaya
mesh_terms: D041721:3T3-L1 Cells; D000818:Animals; D010122:Cystinyl Aminopeptidase / Q000378:metabolism*; D022162:Cytoplasmic Vesicles / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D051275:Glucose Transporter Type 4 / Q000378:metabolism*; D051379:Mice; D021381:Protein Transport; D014746:Vimentin / Q000235:genetics / Q000378:metabolism*
chemical_list: D051275:Glucose Transporter Type 4; C495693:Slc2a4 protein, mouse; D014746:Vimentin; D010122:Cystinyl Aminopeptidase; C105964:leucyl-cystinyl aminopeptidase