| First Author | Cantley LG | Year | 1994 |
| Journal | J Biol Chem | Volume | 269 |
| Issue | 21 | Pages | 15358-61 |
| PubMed ID | 8195174 | Mgi Jnum | J:19020 |
| Mgi Id | MGI:67233 | Doi | 10.1016/s0021-9258(17)36614-0 |
| Citation | Cantley LG, et al. (1994) Ouabain-resistant OR6 cells express the murine alpha 1-subunit of the Na,K-ATPase with a T797-I797 substitution. J Biol Chem 269(21):15358-61 |
| abstractText | Introduction of the murine ouabain resistance gene (Levenson, R., Racaniello, V., Albritton, L., and Housman, D. (1984) Proc. Natl. Acad. Sci. U.S.A. 81, 1489-1493) into African Green monkey CV1 cells reportedly resulted in one cell line, OR6 cells, which was found to be resistant to > 1 mM ouabain (English, L., Epstein, J., Cantley, L., Housman, D., and Levenson, R. (1985) J. Biol. Chem. 260, 1114-1119). The present analysis of the genomic sequence of the alpha 1-subunit of the Na,K-ATPase from OR6 cells reveals copies of the gene for the murine and human alpha 1-subunit of the Na,K-ATPase and not the monkey gene, indicating that the cells have been misidentified. The sequence of the murine alpha 1-subunit from OR6 cells reveals a single point mutation encoding a T797-I797 amino acid substitution at the H6 membrane border. Transfection of CV1 cells with a murine alpha 1 cDNA containing this point mutation resulted in cells with an IC50 for ouabain of approximately 5 mM. These data show that the super ouabain-resistant phenotype of OR6 cells is due to expression of a mutant form of the murine alpha 1-subunit of the sodium pump (rather than the ouabain resistance gene) and further support the recent data suggesting involvement of the H5-H6 domain in ouabain inhibition of the sodium pump. |
