Structural basis for a Ca2+-sensing function of the metabotropic glutamate receptors.
The metabotropic glutamate receptors (mGluRs) are widely distributed in the brain and play important roles in synaptic plasticity. Here it is shown that some types of mGluRs are activated not only by glutamate but also by extracellular Ca2+ (Ca2+o). A single amino acid residue was found to determine the sensitivity of mGluRs to Ca2+o. One of the receptors, mGluR1alpha, but not its point mutant with reduced sensitivity to Ca2+o, caused morphological changes when transfected into mammalian cells. Thus, the sensing of Ca2+o by mGluRs may be important in cells under physiological condition.
Kubo
Y
Y
Department of Neurophysiology, Tokyo Metropolitan Institute for Neuroscience, Musashidai 2-6, Fuchu, Tokyo 183-8526, Japan. ykubo@tmin.ac.jp
Miyashita
T
T
Murata
Y
Y
D000199:Actins / Q000648:ultrastructure; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001921:Brain / Q000378:metabolism; D016466:CHO Cells; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D048429:Cell Size; D006224:Cricetinae; D000242:Cyclic AMP / Q000378:metabolism; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D018698:Glutamic Acid / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D009865:Oocytes; D017354:Point Mutation; D015221:Potassium Channels / Q000378:metabolism; D024661:Potassium Channels, Inwardly Rectifying; D051381:Rats; D018094:Receptors, Metabotropic Glutamate / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015290:Second Messenger Systems; D014162:Transfection; D014982:Xenopus laevis
D000199:Actins; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D018094:Receptors, Metabotropic Glutamate; D011993:Recombinant Fusion Proteins; D018698:Glutamic Acid; D000242:Cyclic AMP; D002118:Calcium