Agonist-specific requirement for a glutamate in transmembrane helix 1 of the oxytocin receptor

Denise L Wootten, John Simms, Amelia J Massoura, Julie E Trim, Mark Wheatley

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Defining key differences between agonist and antagonist binding to hormone receptors is important and will aid rational drug design. Glu(1.35) in transmembrane helix 1 (TM1) of the human oxytocin receptor (OTR) is absolutely conserved in all OTRs cloned to date. We establish that Glu(1.35) is critical for high affinity binding of agonists (full and partial) but is not required for antagonist binding (peptide or non-peptide). Consequently, the mutant receptor [E1.35A]OTR exhibited markedly decreased OT affinity (>1200-fold) and disrupted second messenger generation. Substitutions of Glu(1.35) by Asp, Gln or Arg were incapable of supporting wild-type OTR agonist binding or signaling. Molecular modeling revealed that Glu(1.35) projects into the receptor's central binding crevice and provides agonist-specific contacts not utilized by antagonists. This study explains why Glu is absolutely conserved at residue-1.35 in all receptors binding OT and related peptides, and provides molecular insight into key differences between agonist-receptor and antagonist-receptor binding modes.

Original languageEnglish
Pages (from-to)20-27
Number of pages8
JournalMolecular and Cellular Endocrinology
Volume333
Issue number1
DOIs
Publication statusPublished - 10 Feb 2011

Fingerprint

Oxytocin Receptors
Glutamic Acid
Peptides
Drug Design
Second Messenger Systems
Viperidae
Hormones
human OXTR protein

Keywords

  • Amino Acid Sequence
  • Amino Acid Substitution
  • Arginine
  • Asparagine
  • Binding Sites
  • Cell Line
  • Enzyme-Linked Immunosorbent Assay
  • Glutamic Acid
  • Humans
  • Membrane Proteins
  • Models, Molecular
  • Mutation
  • Oxytocin
  • Protein Binding
  • Protein Structure, Secondary
  • Receptors, Oxytocin
  • Signal Transduction
  • Journal Article
  • Research Support, Non-U.S. Gov't

Cite this

Agonist-specific requirement for a glutamate in transmembrane helix 1 of the oxytocin receptor. / Wootten, Denise L; Simms, John; Massoura, Amelia J; Trim, Julie E; Wheatley, Mark.

In: Molecular and Cellular Endocrinology, Vol. 333, No. 1, 10.02.2011, p. 20-27.

Research output: Contribution to journalArticle

Wootten, Denise L ; Simms, John ; Massoura, Amelia J ; Trim, Julie E ; Wheatley, Mark. / Agonist-specific requirement for a glutamate in transmembrane helix 1 of the oxytocin receptor. In: Molecular and Cellular Endocrinology. 2011 ; Vol. 333, No. 1. pp. 20-27.
@article{9787d062f1984eed9738d14dc975bf9d,
title = "Agonist-specific requirement for a glutamate in transmembrane helix 1 of the oxytocin receptor",
abstract = "Defining key differences between agonist and antagonist binding to hormone receptors is important and will aid rational drug design. Glu(1.35) in transmembrane helix 1 (TM1) of the human oxytocin receptor (OTR) is absolutely conserved in all OTRs cloned to date. We establish that Glu(1.35) is critical for high affinity binding of agonists (full and partial) but is not required for antagonist binding (peptide or non-peptide). Consequently, the mutant receptor [E1.35A]OTR exhibited markedly decreased OT affinity (>1200-fold) and disrupted second messenger generation. Substitutions of Glu(1.35) by Asp, Gln or Arg were incapable of supporting wild-type OTR agonist binding or signaling. Molecular modeling revealed that Glu(1.35) projects into the receptor's central binding crevice and provides agonist-specific contacts not utilized by antagonists. This study explains why Glu is absolutely conserved at residue-1.35 in all receptors binding OT and related peptides, and provides molecular insight into key differences between agonist-receptor and antagonist-receptor binding modes.",
keywords = "Amino Acid Sequence, Amino Acid Substitution, Arginine, Asparagine, Binding Sites, Cell Line, Enzyme-Linked Immunosorbent Assay, Glutamic Acid, Humans, Membrane Proteins, Models, Molecular, Mutation, Oxytocin, Protein Binding, Protein Structure, Secondary, Receptors, Oxytocin, Signal Transduction, Journal Article, Research Support, Non-U.S. Gov't",
author = "Wootten, {Denise L} and John Simms and Massoura, {Amelia J} and Trim, {Julie E} and Mark Wheatley",
note = "Copyright {\circledC} 2010 Elsevier Ireland Ltd. All rights reserved.",
year = "2011",
month = "2",
day = "10",
doi = "10.1016/j.mce.2010.11.029",
language = "English",
volume = "333",
pages = "20--27",
journal = "Molecular Endocrinology",
issn = "0303-7207",
publisher = "Elsevier",
number = "1",

}

TY - JOUR

T1 - Agonist-specific requirement for a glutamate in transmembrane helix 1 of the oxytocin receptor

AU - Wootten, Denise L

AU - Simms, John

AU - Massoura, Amelia J

AU - Trim, Julie E

AU - Wheatley, Mark

N1 - Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

PY - 2011/2/10

Y1 - 2011/2/10

N2 - Defining key differences between agonist and antagonist binding to hormone receptors is important and will aid rational drug design. Glu(1.35) in transmembrane helix 1 (TM1) of the human oxytocin receptor (OTR) is absolutely conserved in all OTRs cloned to date. We establish that Glu(1.35) is critical for high affinity binding of agonists (full and partial) but is not required for antagonist binding (peptide or non-peptide). Consequently, the mutant receptor [E1.35A]OTR exhibited markedly decreased OT affinity (>1200-fold) and disrupted second messenger generation. Substitutions of Glu(1.35) by Asp, Gln or Arg were incapable of supporting wild-type OTR agonist binding or signaling. Molecular modeling revealed that Glu(1.35) projects into the receptor's central binding crevice and provides agonist-specific contacts not utilized by antagonists. This study explains why Glu is absolutely conserved at residue-1.35 in all receptors binding OT and related peptides, and provides molecular insight into key differences between agonist-receptor and antagonist-receptor binding modes.

AB - Defining key differences between agonist and antagonist binding to hormone receptors is important and will aid rational drug design. Glu(1.35) in transmembrane helix 1 (TM1) of the human oxytocin receptor (OTR) is absolutely conserved in all OTRs cloned to date. We establish that Glu(1.35) is critical for high affinity binding of agonists (full and partial) but is not required for antagonist binding (peptide or non-peptide). Consequently, the mutant receptor [E1.35A]OTR exhibited markedly decreased OT affinity (>1200-fold) and disrupted second messenger generation. Substitutions of Glu(1.35) by Asp, Gln or Arg were incapable of supporting wild-type OTR agonist binding or signaling. Molecular modeling revealed that Glu(1.35) projects into the receptor's central binding crevice and provides agonist-specific contacts not utilized by antagonists. This study explains why Glu is absolutely conserved at residue-1.35 in all receptors binding OT and related peptides, and provides molecular insight into key differences between agonist-receptor and antagonist-receptor binding modes.

KW - Amino Acid Sequence

KW - Amino Acid Substitution

KW - Arginine

KW - Asparagine

KW - Binding Sites

KW - Cell Line

KW - Enzyme-Linked Immunosorbent Assay

KW - Glutamic Acid

KW - Humans

KW - Membrane Proteins

KW - Models, Molecular

KW - Mutation

KW - Oxytocin

KW - Protein Binding

KW - Protein Structure, Secondary

KW - Receptors, Oxytocin

KW - Signal Transduction

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1016/j.mce.2010.11.029

DO - 10.1016/j.mce.2010.11.029

M3 - Article

VL - 333

SP - 20

EP - 27

JO - Molecular Endocrinology

JF - Molecular Endocrinology

SN - 0303-7207

IS - 1

ER -