Human BTR1, a new bicarbonate transporter superfamily member and human AE4 from kidney

Biochem Biophys Res Commun. 2001 Apr 20;282(5):1103-9. doi: 10.1006/bbrc.2001.4692.


We report the cloning, characterization, and chromosomal localization of two novel human members of the bicarbonate transporter superfamily, BTR1 (Bicarbonate Transporter Related protein-1) and AE4 (Anion Exchange protein 4). BTR1 is a novel mammalian protein. The BTR1 gene maps to chromosome 20p12 and encodes a 100 kDa protein predominantly expressed in the kidney, salivary glands, testis, thyroid glands, and trachea. The AE4 gene maps to chromosome 5q23-31 and encodes a 104 kDa protein expressed mainly in the kidney. Human AE4 shares 84% identity with the recently reported rabbit AE4, a sodium independent, Cl(-)/HCO(-)(3) exchanger located on the apical membrane of beta-intercalated kidney cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs / genetics
  • Anion Transport Proteins*
  • Antiporters / genetics*
  • Antiporters / metabolism
  • Bicarbonates / metabolism
  • Cell-Free System
  • Chloride-Bicarbonate Antiporters*
  • Chromosomes, Human, Pair 20 / genetics
  • Chromosomes, Human, Pair 5 / genetics
  • Cloning, Molecular
  • Glycosylation
  • Humans
  • Ion Pumps / genetics
  • Ion Pumps / metabolism
  • Kidney / metabolism*
  • Molecular Sequence Data
  • Multigene Family
  • Organ Specificity
  • Physical Chromosome Mapping
  • Protein Biosynthesis
  • Sequence Homology, Amino Acid
  • Sodium-Bicarbonate Symporters


  • Anion Transport Proteins
  • Antiporters
  • Bicarbonates
  • Chloride-Bicarbonate Antiporters
  • Ion Pumps
  • SLC4A11 protein, human
  • SLC4A9 protein, human
  • Sodium-Bicarbonate Symporters

Associated data

  • GENBANK/AF336127
  • GENBANK/AF336237