title: Association of the brain anion exchanger, AE3, with the repeat domain of ankyrin.
abstract: The 89 kDa NH2-terminal domain of erythrocyte ankyrin is composed almost entirely of 22 tandem repeats of a 33 amino acid sequence and constitutes the binding site for the cytoplasmic NH2-terminal domain of the erythrocyte anion exchanger, AE1. We have developed an assay to evaluate the in vivo interaction between a fragment of ankyrin corresponding to this domain (ANK90) and two non-erythroid anion exchangers, AE2 and AE3, that share considerable structural homology with AE1. Association was assessed by co-immunoprecipitation of ANK90-anion exchanger complexes from detergent extracts of cells cotransfected with plasmids encoding the ankyrin fragment and the anion exchanger or mutants thereof. ANK90 was co-immunoprecipitated with AE1 but not with an AE1 deletion mutant lacking the cytoplasmic NH2-terminal domain. Using this assay, we show that the brain anion exchanger AE3, but not the closely related homologue, AE2, is capable of binding to ankyrin.
authors.affiliation: Department of Biological Sciences, Stanford University, CA 94305-5020.
authors.forename: C W
authors.initials: CW
authors.lastname: Morgans
authors.forename: R R
authors.initials: RR
authors.lastname: Kopito
mesh_terms: D027321:Anion Transport Proteins; D017487:Ankyrins / Q000235:genetics / Q000378:metabolism*; D017920:Antiporters; D001483:Base Sequence; D001665:Binding Sites; D001921:Brain / Q000378:metabolism*; D002460:Cell Line; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid; D064606:SLC4A Proteins; D014162:Transfection
chemical_list: D027321:Anion Transport Proteins; D017487:Ankyrins; D017920:Antiporters; D018076:DNA, Complementary; D008565:Membrane Proteins; D064606:SLC4A Proteins; C489237:SLC4A3 protein, human