Effects of a calcimimetic compound and naturally activating mutations on the human Ca2+ receptor and on Ca2+ receptor/metabotropic glutamate chimeric receptors

O. M. Hauache, J. Hu, K. Ray, R. Xie, K. A. Jacobson, Allen M. Spiegel

Research output: Contribution to journalArticle

74 Citations (Scopus)

Abstract

Naturally occurring mutations identified in subjects with autosomal dominant hypocalcemia (ADH) and the calcimimetic compound, R-568, have both been reported to increase Ca2+ sensitivity of the Ca2+ receptor (CaR). To gain insight into their mechanism of action, we studied interactions between four different ADH mutations located in the amino-terminal extracellular domain (ECD) and R-568. We found that R-568 increased the sensitivity of three of the ADH mutant receptors, but the Leu125Pro mutant appeared to be maximally left-shifted in that neither R-568 addition nor combining other ADH mutations with Leu125Pro gave increases in sensitivity comparable to those seen with the three other ADH mutations studied. We also made use of truncation and deletion mutants of the CaR and CaR/metabotropic glutamate receptor type 1 (mGluR1) chimeras to study both the site of action of R-568 and the effect of the Leu125Pro activating mutation. R-568 was effective in receptor constructs containing the seven transmembrane domain (7TM) of the CaR, but not in those containing the mGluR1 7TM. R-568, moreover, imparted Ca2+ responsiveness to CaR constructs lacking all or part of the CaR ECD. The Leu125Pro mutation in contrast conferred no or minimal increase in Ca2+ responsiveness to CaR constructs lacking part of the CaR ECD but showed a striking increase in basal activity in the context of chimeras containing an mGluR1 7TM. Our results localize the site of action of NPS-568 specifically to the CaR 7TM. Our results with the Leu125Pro mutant, furthermore, suggest that the mGluR1 7TM domain may be more permissive for activation than the 7TM domain of the CaR.

Original languageEnglish (US)
Pages (from-to)4156-4163
Number of pages8
JournalEndocrinology
Volume141
Issue number11
StatePublished - 2000
Externally publishedYes

Fingerprint

N-(2-chlorophenylpropyl)-1-(3-methoxyphenyl)ethylamine
Glutamate Receptors
Mutation
Familial Hypercalciuric Hypocalcemia

ASJC Scopus subject areas

  • Endocrinology
  • Endocrinology, Diabetes and Metabolism

Cite this

Effects of a calcimimetic compound and naturally activating mutations on the human Ca2+ receptor and on Ca2+ receptor/metabotropic glutamate chimeric receptors. / Hauache, O. M.; Hu, J.; Ray, K.; Xie, R.; Jacobson, K. A.; Spiegel, Allen M.

In: Endocrinology, Vol. 141, No. 11, 2000, p. 4156-4163.

Research output: Contribution to journalArticle

@article{57a3e490a4104a128360f4ebc2751525,
title = "Effects of a calcimimetic compound and naturally activating mutations on the human Ca2+ receptor and on Ca2+ receptor/metabotropic glutamate chimeric receptors",
abstract = "Naturally occurring mutations identified in subjects with autosomal dominant hypocalcemia (ADH) and the calcimimetic compound, R-568, have both been reported to increase Ca2+ sensitivity of the Ca2+ receptor (CaR). To gain insight into their mechanism of action, we studied interactions between four different ADH mutations located in the amino-terminal extracellular domain (ECD) and R-568. We found that R-568 increased the sensitivity of three of the ADH mutant receptors, but the Leu125Pro mutant appeared to be maximally left-shifted in that neither R-568 addition nor combining other ADH mutations with Leu125Pro gave increases in sensitivity comparable to those seen with the three other ADH mutations studied. We also made use of truncation and deletion mutants of the CaR and CaR/metabotropic glutamate receptor type 1 (mGluR1) chimeras to study both the site of action of R-568 and the effect of the Leu125Pro activating mutation. R-568 was effective in receptor constructs containing the seven transmembrane domain (7TM) of the CaR, but not in those containing the mGluR1 7TM. R-568, moreover, imparted Ca2+ responsiveness to CaR constructs lacking all or part of the CaR ECD. The Leu125Pro mutation in contrast conferred no or minimal increase in Ca2+ responsiveness to CaR constructs lacking part of the CaR ECD but showed a striking increase in basal activity in the context of chimeras containing an mGluR1 7TM. Our results localize the site of action of NPS-568 specifically to the CaR 7TM. Our results with the Leu125Pro mutant, furthermore, suggest that the mGluR1 7TM domain may be more permissive for activation than the 7TM domain of the CaR.",
author = "Hauache, {O. M.} and J. Hu and K. Ray and R. Xie and Jacobson, {K. A.} and Spiegel, {Allen M.}",
year = "2000",
language = "English (US)",
volume = "141",
pages = "4156--4163",
journal = "Endocrinology",
issn = "0013-7227",
publisher = "The Endocrine Society",
number = "11",

}

TY - JOUR

T1 - Effects of a calcimimetic compound and naturally activating mutations on the human Ca2+ receptor and on Ca2+ receptor/metabotropic glutamate chimeric receptors

AU - Hauache, O. M.

AU - Hu, J.

AU - Ray, K.

AU - Xie, R.

AU - Jacobson, K. A.

AU - Spiegel, Allen M.

PY - 2000

Y1 - 2000

N2 - Naturally occurring mutations identified in subjects with autosomal dominant hypocalcemia (ADH) and the calcimimetic compound, R-568, have both been reported to increase Ca2+ sensitivity of the Ca2+ receptor (CaR). To gain insight into their mechanism of action, we studied interactions between four different ADH mutations located in the amino-terminal extracellular domain (ECD) and R-568. We found that R-568 increased the sensitivity of three of the ADH mutant receptors, but the Leu125Pro mutant appeared to be maximally left-shifted in that neither R-568 addition nor combining other ADH mutations with Leu125Pro gave increases in sensitivity comparable to those seen with the three other ADH mutations studied. We also made use of truncation and deletion mutants of the CaR and CaR/metabotropic glutamate receptor type 1 (mGluR1) chimeras to study both the site of action of R-568 and the effect of the Leu125Pro activating mutation. R-568 was effective in receptor constructs containing the seven transmembrane domain (7TM) of the CaR, but not in those containing the mGluR1 7TM. R-568, moreover, imparted Ca2+ responsiveness to CaR constructs lacking all or part of the CaR ECD. The Leu125Pro mutation in contrast conferred no or minimal increase in Ca2+ responsiveness to CaR constructs lacking part of the CaR ECD but showed a striking increase in basal activity in the context of chimeras containing an mGluR1 7TM. Our results localize the site of action of NPS-568 specifically to the CaR 7TM. Our results with the Leu125Pro mutant, furthermore, suggest that the mGluR1 7TM domain may be more permissive for activation than the 7TM domain of the CaR.

AB - Naturally occurring mutations identified in subjects with autosomal dominant hypocalcemia (ADH) and the calcimimetic compound, R-568, have both been reported to increase Ca2+ sensitivity of the Ca2+ receptor (CaR). To gain insight into their mechanism of action, we studied interactions between four different ADH mutations located in the amino-terminal extracellular domain (ECD) and R-568. We found that R-568 increased the sensitivity of three of the ADH mutant receptors, but the Leu125Pro mutant appeared to be maximally left-shifted in that neither R-568 addition nor combining other ADH mutations with Leu125Pro gave increases in sensitivity comparable to those seen with the three other ADH mutations studied. We also made use of truncation and deletion mutants of the CaR and CaR/metabotropic glutamate receptor type 1 (mGluR1) chimeras to study both the site of action of R-568 and the effect of the Leu125Pro activating mutation. R-568 was effective in receptor constructs containing the seven transmembrane domain (7TM) of the CaR, but not in those containing the mGluR1 7TM. R-568, moreover, imparted Ca2+ responsiveness to CaR constructs lacking all or part of the CaR ECD. The Leu125Pro mutation in contrast conferred no or minimal increase in Ca2+ responsiveness to CaR constructs lacking part of the CaR ECD but showed a striking increase in basal activity in the context of chimeras containing an mGluR1 7TM. Our results localize the site of action of NPS-568 specifically to the CaR 7TM. Our results with the Leu125Pro mutant, furthermore, suggest that the mGluR1 7TM domain may be more permissive for activation than the 7TM domain of the CaR.

UR - http://www.scopus.com/inward/record.url?scp=0033679325&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033679325&partnerID=8YFLogxK

M3 - Article

C2 - 11089548

AN - SCOPUS:0033679325

VL - 141

SP - 4156

EP - 4163

JO - Endocrinology

JF - Endocrinology

SN - 0013-7227

IS - 11

ER -