In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 90, No. 17 ( 1993-09), p. 8073-8077
Abstract:
Injection of rat kidney cortex mRNA into Xenopus laevis oocytes leads to a stimulation of Na(+)-dependent SO4(2-) uptake. Based on this information, we have isolated from a corresponding library a cDNA (NaSi-1) that is most likely related to a Na+/SO4(2-) cotransport system. NaSi-1 cRNA leads in a time- and dose-dependent manner to specific stimulation of Na(+)-dependent SO4(2-) uptake in oocytes. The apparent affinity constants of the NaSi-1 cRNA-expressed transport resemble those of Na+/SO4(2-) cotransport in brush-border membrane. The NaSi-1 cDNA contains 2239 bp [including a poly(A) tail] and encodes a protein of 595 amino acids (66.05 kDa); the hydropathy profile suggests at least eight membrane-spanning regions. In vitro translation of NaSi-1 cRNA results in a protein of the expected size and suggests glycosylation. Northern blot analysis shows signals of 2.3 and 2.9 kb in kidney (more abundant in cortex than in papilla/medulla) and in mucosa of small intestine of rats. The above data indicate that we have structurally identified a membrane protein involved in renal and small-intestinal brush-border membrane Na+/SO4(2-) cotransport.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.90.17.8073
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
1993
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
