title: Cloning and characterization of band 3, the human erythrocyte anion-exchange protein (AE1).
abstract: The human erythrocyte anion-exchange protein (band 3 or AE1) was cloned from a fetal liver cDNA library. Three overlapping clones, encompassing 3637 nucleotides, were analyzed in detail. These encode a 911-amino acid protein (Mr 101,791) and detect a single 4.7-kilobase species in human reticulocyte RNA. The corresponding gene is located on chromosome 17. The protein is similar in structure to other anion exchangers and is divided into three regions: a hydrophilic, cytoplasmic domain that interacts with a variety of membrane and cytoplasmic proteins (residues 1-403); a hydrophobic, transmembrane domain that forms the anion antiporter (residues 404-882); and an acidic, C-terminal domain of unknown function (residues 883-911). The N-terminal domain contains several conserved sections (e.g., residues 57-86, 102-164, 219-347, and 375-403), some of which may contribute to binding sites for ankyrin, protein 4.1, or protein 4.2. The membrane domain is highly conserved with the exception of a single segment (residues 543-567) that contains several sites for cleavage of the protein by extracellular proteases. Based on hydropathy analyses and the wealth of available topographical and functional data, a model is proposed in which the protein crosses the membrane 14 times.
authors.affiliation: Division of Hematology/Oncology, Children's Hospital, Boston, MA 02115.
authors.forename: S E
authors.initials: SE
authors.lastname: Lux
authors.forename: K M
authors.initials: KM
authors.lastname: John
authors.forename: R R
authors.initials: RR
authors.lastname: Kopito
authors.forename: H F
authors.initials: HF
authors.lastname: Lodish
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001457:Anion Exchange Protein 1, Erythrocyte / Q000235:genetics*; D001483:Base Sequence; D002645:Chickens; D003001:Cloning, Molecular / Q000379:methods*; D004910:Erythrocyte Membrane / Q000378:metabolism; D015723:Gene Library; D005796:Genes; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D012333:RNA, Messenger