We report the cloning, sequence analysis, tissue distribution, functional expression, and chromosomal localization of the human pancreatic sodium bicarbonate cotransport protein (pancreatic NBC (pNBC)). The transporter was identified by searching the human expressed sequence tag data base. An I.M.A.G.E. clone W39298 was identified, and a polymerase chain reaction probe was generated to screen a human pancreas cDNA library. pNBC encodes a 1079-residue polypeptide that differs at the N terminus from the recently cloned human sodium bicarbonate cotransporter isolated from kidney (kNBC) (Burnham, C. E., Amlal, H., Wang, Z., Shull, G. E., and Soleimani, M. (1997) J. Biol. Chem. 272, 19111–19114). Northern blot analysis using a probe specific for the N terminus of pNBC revealed an ∼7.7-kilobase transcript expressed predominantly in pancreas, with less expression in kidney, brain, liver, prostate, colon, stomach, thyroid, and spinal chord. In contrast, a probe to the unique 5′ region of kNBC detected an ∼7.6-kilobase transcript only in the kidney. In situhybridization studies in pancreas revealed expression in the acini and ductal cells. The gene was mapped to chromosome 4q21 using fluorescentin situ hybridization. Expression of pNBC in Xenopus laevis oocytes induced sodium bicarbonate cotransport. These data demonstrate that pNBC encodes the sodium bicarbonate cotransporter in the mammalian pancreas. pNBC is also expressed at a lower level in several other organs, whereas kNBC is expressed uniquely in kidney.
Molecular Cloning, Chromosomal Localization, Tissue Distribution, and Functional Expression of the Human Pancreatic Sodium Bicarbonate Cotransporter*
N. Abuladze,I. Lee,D. Newman,James S. Hwang,K. Boorer,A. Pushkin,I. Kurtz
Published 1998 in Journal of Biological Chemistry
ABSTRACT
PUBLICATION RECORD
- Publication year
1998
- Venue
Journal of Biological Chemistry
- Publication date
1998-07-10
- Fields of study
Biology, Medicine
- Identifiers
- External record
- Source metadata
Semantic Scholar, PubMed
CITATION MAP
EXTRACTION MAP
CLAIMS
- No claims are published for this paper.
CONCEPTS
- No concepts are published for this paper.
REFERENCES
Showing 1-43 of 43 references · Page 1 of 1