title: Ablation of the cholesterol transporter adenosine triphosphate-binding cassette transporter G1 reduces adipose cell size and protects against diet-induced obesity.
abstract: The ATP-binding cassette transporter G1 (ABCG1) catalyzes export of cellular cholesterol from macrophages and hepatocytes. Here we identify an additional function of ABCG1 in the regulation of adiposity in screens of the Drosophila melanogaster and the New Zealand obese (NZO) mouse genomes. Insertion of modified transposable elements of the P-family upstream of CG17646, the Drosophila ortholog of Abcg1, generated lines of flies with increased triglyceride stores. In NZO mice, an Abcg1 variant was identified in a suggestive adiposity quantitative trait locus and was associated with higher expression of the gene in white adipose tissue. Targeted disruption of Abcg1 in mice resulted in reduced body weight gain (8.42+/-0.6 g in Abcg1-/- vs. 13.07+/-1.1 g in Abcg1+/+ mice) and adipose tissue mass gain (3.78+/-1.3 g in Abcg1-/- vs. 9.39+/-1.6 g in Abcg1+/+ mice) detected over a period of 12 wk. The reduction of adipose tissue mass in Abcg1-/- mice was associated with markedly decreased size of the adipocytes. In contrast to their wild-type littermates, male Abcg1-/- mice exhibited no high-fat diet-induced impairment of glucose tolerance and fatty liver. Furthermore, Abcg1-/- mice possess decreased food intake and elevated total energy expenditure (Abcg1-/- mice, 748.1+/-5.4 kJ/kg metabolic body mass; Abcg1+/+ mice, 684.3+/-5.0 kJ/kg metabolic body mass; P=0.011), body temperature (Abcg1-/- mice, 37.82+/-0.29 C; Abcg1+/+ mice, 36.83+/-0.24 C; P<0.05), and locomotor activity (Abcg1-/- mice, 3655+/-189 counts/12 h during dark phase; Abcg1+/+ mice, 2445+/-235 counts/12 h during dark phase; P<0.01). Our data indicate a previously unrecognized role of ABCG1 in the regulation of energy balance and triglyceride storage.
authors.affiliation: Department of Pharmacology, German Institute of Human Nutrition, Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, D-14558 Nuthetal, Germany.
authors.forename: Jana
authors.initials: J
authors.lastname: Buchmann
authors.forename: Christoph
authors.initials: C
authors.lastname: Meyer
authors.forename: Susanne
authors.initials: S
authors.lastname: Neschen
authors.forename: Robert
authors.initials: R
authors.lastname: Augustin
authors.forename: Katja
authors.initials: K
authors.lastname: Schmolz
authors.forename: Reinhart
authors.initials: R
authors.lastname: Kluge
authors.forename: Hadi
authors.initials: H
authors.lastname: Al-Hasani
authors.forename: Hella
authors.initials: H
authors.lastname: Jürgens
authors.forename: Karsten
authors.initials: K
authors.lastname: Eulenberg
authors.forename: Roland
authors.initials: R
authors.lastname: Wehr
authors.forename: Cord
authors.initials: C
authors.lastname: Dohrmann
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Joost
authors.forename: Annette
authors.initials: A
authors.lastname: Schürmann
mesh_terms: D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1; D018528:ATP-Binding Cassette Transporters / Q000235:genetics* / Q000502:physiology; D017667:Adipocytes / Q000166:cytology*; D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D001835:Body Weight; D048429:Cell Size; D004032:Diet / Q000009:adverse effects*; D004331:Drosophila melanogaster; D005260:Female; D008074:Lipoproteins / Q000235:genetics* / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008814:Mice, Inbred NZB; D018345:Mice, Knockout; D008820:Mice, Obese; D009765:Obesity / Q000209:etiology / Q000235:genetics / Q000517:prevention & control*
chemical_list: C487540:ABCG1 protein, mouse; D000070998:ATP Binding Cassette Transporter, Subfamily G, Member 1; D018528:ATP-Binding Cassette Transporters; D008074:Lipoproteins