Calcium sensing receptor: molecular cloning in rat and localization to nerve terminals.
We have molecularly cloned a calcium sensing receptor (CaSR) from a rat striatal cDNA library. Rat CaSR displays 92% overall homology to its bovine counterpart with seven putative transmembrane domains characteristic of the superfamily of guanine nucleotide-binding proteins and significant homology with the metabotropic glutamate receptors. Northern blot analysis reveals two transcripts in thyroid, kidney, lung, ileum, and pituitary. In brain highest regional expression of the RNA occurs in the hypothalamus and the corpus striatum. Immunohistochemistry reveals discrete punctate localizations throughout the brain that appear to be associated with nerve terminals. No staining is evident in cell bodies of neurons or glia. Cerebral arteries display an intense network of CaSR immunoreactive fibers associated with vessel innervation. CaSR on nerve terminal membranes may regulate neurotransmitter disposition in response to Ca2+ levels in the synaptic space.
Ruat
M
M
Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Molliver
M E
ME
Snowman
A M
AM
Snyder
S H
SH
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000098:blood supply; D001923:Brain Chemistry; D002118:Calcium / Q000378:metabolism*; D003001:Cloning, Molecular; D003342:Corpus Striatum / Q000737:chemistry; D018076:DNA, Complementary / Q000235:genetics; D007031:Hypothalamus / Q000737:chemistry; D015151:Immunoblotting; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D009411:Nerve Endings / Q000737:chemistry*; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D011487:Protein Conformation; D051381:Rats; D044169:Receptors, Calcium-Sensing; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D014018:Tissue Distribution
D018076:DNA, Complementary; D009419:Nerve Tissue Proteins; D044169:Receptors, Calcium-Sensing; D011956:Receptors, Cell Surface; C473605:extracellular calcium cation-sensing receptor, rat; D002118:Calcium