title: Oligomeric structure of bAE3 protein.
abstract: The "brain" form of the anion exchanger protein 3 (bAE3) has been purified to homogeneity from the rabbit kidney by differential centrifugation and immunoaffinity chromatography. A single protein band of approximately 165 kDa was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. Monomers, dimers (a major component), and a higher oligomeric form (apparently tetramers) were found after oxidative cross-linking of purified bAE3. The largest form of bAE3 was separated from dimers and monomers by sucrose gradient centrifugation and was studied by transmission electron microscopy to confirm a tetrameric structure. Two main types of bAE3 images were detected, round (approximately 11-14 nm) and square-shaped (approximately 12 x 12 nm). Image analysis revealed fourfold rotational symmetry of both the round and square-shaped images, indicating that bAE3 consists of multiples of 4 subunits. We conclude that bAE3 in Triton X-100 solution is predominantly a mixture of dimers and tetramers with a smaller amount of monomers.
authors.affiliation: Division of Nephrology, Center for Health Sciences, UCLA School of Medicine, Los Angeles, California 90095-1689, USA. apushkin@mednet.ucla.edu
authors.forename: A V
authors.initials: AV
authors.lastname: Pushkin
authors.forename: V L
authors.initials: VL
authors.lastname: Tsuprun
authors.forename: N K
authors.initials: NK
authors.lastname: Abuladze
authors.forename: D
authors.initials: D
authors.lastname: Newman
authors.forename: I
authors.initials: I
authors.lastname: Kurtz
mesh_terms: D000818:Animals; D017920:Antiporters / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D007668:Kidney / Q000737:chemistry; D008969:Molecular Sequence Data; D017830:Octoxynol / Q000737:chemistry; D011487:Protein Conformation; D011817:Rabbits
chemical_list: D017920:Antiporters; D017830:Octoxynol