| First Author | Tucker JE | Year | 1998 |
| Journal | Invest Ophthalmol Vis Sci | Volume | 39 |
| Issue | 2 | Pages | 435-40 |
| PubMed ID | 9478004 | Mgi Jnum | J:45787 |
| Mgi Id | MGI:1196117 | Citation | Tucker JE, et al. (1998) cDNA cloning of the human retinal rod Na-Ca + K exchanger: comparison with a revised bovine sequence. Invest Ophthalmol Vis Sci 39(2):435-40 |
| abstractText | PURPOSE: To clone the complementary DNA of the human retinal rod Na-Ca+ K exchanger. METHODS: A human retinal cDNA library was screened initially with a radiolabeled probe representing the entire bovine rod Na-Ca + K exchanger cDNA and subsequently with probes from polymerase chain reaction fragments of the human retinal rod Na-Ca + K exchanger obtained after the initial screen. Twelve positive clones were used to obtain the entire coding sequence of the human retinal rod Na-Ca + K exchanger. RESULTS: The cDNA of the human retinal rod Na-Ca + K exchanger codes for a protein of 1081 amino acids, which shows 64.3% overall identity with the bovine retinal rod Na-Ca + K exchanger at the amino acid level. The two sets of putative transmembrane-spanning domains and their short connecting loops showed the highest degree of identity (94%-95%), whereas the extracellular loop at the N terminus showed a 59% identity. The large cytosolic loop that bisects the two sets of transmembrane-spanning domains contained two large deletions in the human exchanger; the first deletion contains 18 amino acids, whereas the second deletion involves a series of repeats that are dominated by acidic amino acid residues observed in the bovine, but not in the human, sequence. The authors observed that the bovine sequence contains a ninth repeat in addition to the eight repeats of the published sequence. CONCLUSIONS: The authors cloned the cDNA of the human retinal rod Na-Ca + K exchanger as a first step in examining the possibility that this gene could be the locus of disease-causing mutations. |
