title: ABCA3 is a lamellar body membrane protein in human lung alveolar type II cells.
abstract: The ABCA3 gene, of the ABCA subclass of ATP-binding cassette (ABC) transporters, is expressed exclusively in lung. We report here the cloning, molecular characterization, and distribution of human ABCA3 in the lung. Immunoblot analysis using the specific antibody reveals a 150-kDa protein in the crude membrane fraction of human lung. Immunohistochemical analyses of alveoli show that ABCA3 is expressed only in the type II cells expressing surfactant protein A. At the ultrastructural level, ABCA3 immunoreactivity was detected mostly at the limiting membrane of the lamellar bodies. Since members of the ABCA transporter family are known to be involved in transmembrane transport of endogenous lipids, our findings suggest that ABCA3 plays an important role in the formation of pulmonary surfactant in type II cells.
authors.affiliation: Department of Physiology, Akita University School of Medicine, Japan.
authors.forename: G
authors.initials: G
authors.lastname: Yamano
authors.forename: H
authors.initials: H
authors.lastname: Funahashi
authors.forename: O
authors.initials: O
authors.lastname: Kawanami
authors.forename: L X
authors.initials: LX
authors.lastname: Zhao
authors.forename: N
authors.initials: N
authors.lastname: Ban
authors.forename: Y
authors.initials: Y
authors.lastname: Uchida
authors.forename: T
authors.initials: T
authors.lastname: Morohoshi
authors.forename: J
authors.initials: J
authors.lastname: Ogawa
authors.forename: S
authors.initials: S
authors.lastname: Shioda
authors.forename: N
authors.initials: N
authors.lastname: Inagaki
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000032:analysis / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D000906:Antibodies / Q000276:immunology; D015153:Blotting, Western; D002460:Cell Line; D003001:Cloning, Molecular; D006801:Humans; D007150:Immunohistochemistry; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009928:Organ Specificity; D011510:Proteolipids / Q000378:metabolism; D011650:Pulmonary Alveoli / Q000166:cytology* / Q000378:metabolism* / Q000648:ultrastructure; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000096:biosynthesis / Q000378:metabolism
chemical_list: C441524:ABCA3 protein, human; D018528:ATP-Binding Cassette Transporters; D000906:Antibodies; D011510:Proteolipids; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants