TY - JOUR
T1 - Role of the large extracellular domain of metabotropic glutamate receptors in agonist selectivity determination
AU - Takahashi, K.
AU - Tsuchida, K.
AU - Tanabe, Y.
AU - Masu, M.
AU - Nakanishi, S.
N1 - Copyright:
Copyright 2004 Elsevier B.V., All rights reserved.
PY - 1993
Y1 - 1993
N2 - Metabotropic glutamate receptors consist of at least six different subtypes termed mGluR1-mGluR6. They belong to the family of G protein- coupled receptors and commonly possess an unusually large extracellular domain preceding the seven transmembrane segments, mGluR1 and mGluR2 show similar affinities for L-glutamate but distinct patterns in their responsiveness to quisqualate and trans-1-amino-1,3-cyclopentanedicarboxylate (tACPD). To assign structural determinants for the different agonist selectivities, we constructed a series of chimeric receptors at the extracellular domains of mGluR1 and mGluR2 and determined their agonist selectivities by measuring their electrophysiological responses to L- glutamate, quisqualate, and tACPD in Xenopus oocytes. Replacement of the extracellular domain up to about one-half of the amino-terminal extracellular domain of mGluR1 with the corresponding portion of mGluR2 generated a pattern of the agonist selectivity characteristic of mGluR2. The acquirement of this property in agonist selectivity was further indicated by the selective responses of these chimeric receptors to an mGluR2-specific agonist, (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine. This investigation demonstrates that the extracellular domain of mGluR is critical in determining agonist selectivity and that the mode of determination of agonist selectivity of mGluR is different from that of other G protein-coupled receptors for small molecule transmitters.
AB - Metabotropic glutamate receptors consist of at least six different subtypes termed mGluR1-mGluR6. They belong to the family of G protein- coupled receptors and commonly possess an unusually large extracellular domain preceding the seven transmembrane segments, mGluR1 and mGluR2 show similar affinities for L-glutamate but distinct patterns in their responsiveness to quisqualate and trans-1-amino-1,3-cyclopentanedicarboxylate (tACPD). To assign structural determinants for the different agonist selectivities, we constructed a series of chimeric receptors at the extracellular domains of mGluR1 and mGluR2 and determined their agonist selectivities by measuring their electrophysiological responses to L- glutamate, quisqualate, and tACPD in Xenopus oocytes. Replacement of the extracellular domain up to about one-half of the amino-terminal extracellular domain of mGluR1 with the corresponding portion of mGluR2 generated a pattern of the agonist selectivity characteristic of mGluR2. The acquirement of this property in agonist selectivity was further indicated by the selective responses of these chimeric receptors to an mGluR2-specific agonist, (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine. This investigation demonstrates that the extracellular domain of mGluR is critical in determining agonist selectivity and that the mode of determination of agonist selectivity of mGluR is different from that of other G protein-coupled receptors for small molecule transmitters.
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M3 - Article
C2 - 8103516
AN - SCOPUS:0027282265
VL - 268
SP - 19341
EP - 19345
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 26
ER -