Human BTR1, a new bicarbonate transporter superfamily member and human AE4 from kidney
M D Parker1, E P Ourmozdi, M J Tanner
1Department of Biochemistry, School of Medical Sciences, University of Bristol, University Walk, Bristol, BS8 1TD, United Kingdom.
Abstract:
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.
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