Cloning and functional expression of a rat kidney extracellular calcium/polyvalent cation-sensing receptor.
- 3 January 1995
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 92 (1), 131-135
- https://doi.org/10.1073/pnas.92.1.131
Abstract
The maintenance of a stable extracellular concentration of ionized calcium depends on the integrated function of a number of specialized cells (e.g., parathyroid and certain kidney epithelial cells). We recently identified another G protein-coupled receptor (BoPCaRI) from bovine parathyroid that responds to changes in extracellular Ca2+ within the millimolar range and provides a key mechanism for regulating the secretion of parathyroid hormone. Using an homology-based strategy, we now report the isolation of a cDNA encoding an extracellular Ca2+/polyvalent cation-sensing receptor (RaKCaR) from rat kidney. The predicted RaKCaR protein shares 92% identity with BoPCaR1 receptor and features a seven membrane-spanning domain, characteristic of the G protein-coupled receptors, which is preceded by a large hydrophilic extracellular NH2 terminus believed to be involved in cation binding. RaKCaR cRNA-injected Xenopus oocytes responded to extracellular Ca2+, Mg2+, Gd3+, and neomycin with characteristic activation of inositol phospholipid-dependent, intracellular Ca(2+)-induced Cl- currents. In rat kidney, Northern analysis revealed RaKCaR transcripts of 4 and 7 kb, and in situ hybridization showed localization primarily in outer medulla and cortical medullary rays. Our results provide important insights into the molecular structure of an extracellular Ca2+/polyvalent cation-sensing receptor in rat kidney and provide another basis on which to understand the role of extracellular divalent cations in regulating kidney function in mineral metabolism.Keywords
This publication has 33 references indexed in Scilit:
- Cloning and characterization of an extracellular Ca2+-sensing receptor from bovine parathyroidNature, 1993
- The ligand-binding domain in metabotropic glutamate receptors is related to bacterial periplasmic binding proteinsNeuron, 1993
- Cloning and expression of an inwardly rectifying ATP-regulated potassium channelNature, 1993
- Molecular Diversity of Glutamate Receptors and Implications for Brain FunctionScience, 1992
- Regulation of 1,25-dihydroxyvitamin d3 by calcium in the parathyroidectomized, parathyroid hormone-replete ratJournal of Bone and Mineral Research, 1989
- Inhibitory guanosine triphosphate-binding protein-mediated regulation of vasopressin action in isolated single medullary tubules of mouse kidney.JCI Insight, 1988
- The Use ofXenopusOocytes for the Study of Ion ChannelCritical Reviews in Biochemistry, 1987
- Cytosolic Ca2+ and the regulation of secretion in parathyroid cellsFEBS Letters, 1986
- A simple method for displaying the hydropathic character of a proteinJournal of Molecular Biology, 1982
- Inhibitory effects of hypermagnesemia on the renal action of parathyroid hormone.JCI Insight, 1976