title: Each of the four intracellular cysteines of CD36 is essential for insulin- or AMP-activated protein kinase-induced CD36 translocation.
abstract: Stimulation of cellular fatty acid uptake by induction of insulin signalling or AMP-kinase (AMPK) activation is due to translocation of the fatty acid-transporter CD36 from intracellular stores to the plasma membrane (PM). For investigating the role of the four Cys-residues within CD36's cytoplasmic tails in CD36 translocation, we constructed CHO-cells expressing CD36 mutants in which all four, two, or one of the intracellular Cys were replaced by Ser. Intracellular and PM localization of all mutants was similar to wild-type CD36 (CD36wt). Hence, the four Cys do not regulate sub-cellular CD36 localization. However, in contrast to CD36wt, insulin or AMPK activation failed to induce translocation of any of the mutants, indicating that all four intracellular Cys residues are essential for CD36 translocation. The mechanism of defective translocation of mutant CD36 is unknown, but appears not due to loss of S-palmitoylation of the cytoplasmic tails or to aberrant oligomerization of the mutants.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Biology and Institute of Biomembranes, Utrecht University , NL-3584 CH Utrecht , The Netherlands and.
authors.forename: Masja M
authors.initials: MM
authors.lastname: van Oort
authors.forename: Rinske
authors.initials: R
authors.lastname: Drost
authors.forename: Linda
authors.initials: L
authors.lastname: Janβen
authors.forename: Jan M
authors.initials: JM
authors.lastname: Van Doorn
authors.forename: Jana
authors.initials: J
authors.lastname: Kerver
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Van der Horst
authors.forename: Joost J F P
authors.initials: JJ
authors.lastname: Luiken
authors.forename: Kees C W
authors.initials: KC
authors.lastname: Rodenburg
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D018955:CD36 Antigens / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D003545:Cysteine; D007328:Insulin / Q000378:metabolism*; D042541:Intracellular Space / Q000378:metabolism*; D009154:Mutation; D021381:Protein Transport
chemical_list: D018955:CD36 Antigens; D007328:Insulin; D055372:AMP-Activated Protein Kinases; D003545:Cysteine