title: ABCA3-mediated choline-phospholipids uptake into intracellular vesicles in A549 cells.
abstract: ABCA3 is proposed to function as a lung surfactant lipid transporter. Here we report ABCA3-dependent lipid uptake into intracellular vesicles in lung adenocarcinoma A549 cells. A549 cells stably expressing GFP-tagged wild-type ABCA3 (A549/ABCA3(WT)) had larger LAMP3-positive vesicles than their parental cells as well as A549 cells expressing a Walker A motif mutant (A549/ABCA3(N568D)). The choline-phospholipids level in A549/ABCA3(WT) was increased 1.25-fold compared to that in A549 and A549/ABCA3(N568D) cells, while the cholesterol levels were similar. Sucrose gradient fractionation analysis in A549/ABCA3(WT) cells revealed that choline-phospholipids were enriched in low-density and nile red-positive vesicles. Electronmicroscopic analysis showed multilamellar vesicles in A549/ABCA3(WT) cells. These results indicate that ABCA3 mediates ATP-dependent choline-phospholipids uptake into intracellular vesicles.
authors.affiliation: Department of Physiology, Akita University School of Medicine, Akita, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Matsumura
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Sakai
authors.forename: Mayumi
authors.initials: M
authors.lastname: Sasaki
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Ban
authors.forename: Nobuya
authors.initials: N
authors.lastname: Inagaki
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology*; D000818:Animals; D002784:Cholesterol / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology*; D051907:Lysosomal Membrane Proteins / Q000378:metabolism; D051379:Mice; D009363:Neoplasm Proteins / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D022161:Transport Vesicles / Q000378:metabolism* / Q000648:ultrastructure; D014407:Tumor Cells, Cultured; D059666:Lysosomal-Associated Membrane Protein 3
chemical_list: D018528:ATP-Binding Cassette Transporters; D002784:Cholesterol; D049452:Green Fluorescent Proteins; D051907:Lysosomal Membrane Proteins; D009363:Neoplasm Proteins; D010713:Phosphatidylcholines; D011993:Recombinant Fusion Proteins; C441524:ABCA3 protein, human; C114233:LAMP3 protein, human; D059666:Lysosomal-Associated Membrane Protein 3; C011246:essential 303 forte