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High-affinity binding of peptide agonists to the human B1 bradykinin receptor depends on interaction between the peptide N-terminal L-lysine and the fourth extracellular domain of the receptor

Fathy, Dana B.; Kyle, Donald J. and Leeb-Lundberg, Fredrik LU (2000) In Molecular Pharmacology 57(1). p.171-179
Abstract

The aim of this study was to identify the location of the N terminus of peptide agonist ligands when bound to the human B1 bradykinin (BK) receptor. To reach this aim, we exploited the fact that high-affinity binding of kinin peptides to the human B1 receptor subtype requires a peptide N-terminal L- Lys, whereas high-affinity binding to the B2 receptor subtype does not require this residue. This was done by comparing the affinities of BK, a B2 receptor-selective peptide, and kallidin or Lys-BK, a less receptor-selective peptide, for chimeric proteins in which each B1 receptor domain had been substituted in the human B2 receptor and expressed in HEK293 cells. Individual substitution of transmembrane domains 1-7 (TM-I-VlI) and... (More)

The aim of this study was to identify the location of the N terminus of peptide agonist ligands when bound to the human B1 bradykinin (BK) receptor. To reach this aim, we exploited the fact that high-affinity binding of kinin peptides to the human B1 receptor subtype requires a peptide N-terminal L- Lys, whereas high-affinity binding to the B2 receptor subtype does not require this residue. This was done by comparing the affinities of BK, a B2 receptor-selective peptide, and kallidin or Lys-BK, a less receptor-selective peptide, for chimeric proteins in which each B1 receptor domain had been substituted in the human B2 receptor and expressed in HEK293 cells. Individual substitution of transmembrane domains 1-7 (TM-I-VlI) and extracellular domains 1-4 (EC-I-IV) of the B1 receptor in the B2 receptor influenced the affinities of BK and Lys-BK approximately equally. In contrast, substitution of B1 EC-IV dramatically reduced the affinity and potency of BK, whereas these parameters for Lys-BK were essentially unaltered. Substitution of either the N- or C-terminal half of B1 EC-IV in the B2 receptor only had a limited effect on the peptide binding constants, indicating the involvement of multiple residues throughout this domain. Complementary mutations of the N-terminal residue in Lys-BK revealed that both the positive charge and the proper spatial orientation of this residue were required for interaction with B1 EC-IV. Thus, the N-terminal residue of peptide agonists when bound to the human B1 receptor is positioned extracellularly and interacts with EC-IV.

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author
publishing date
type
Contribution to journal
publication status
published
in
Molecular Pharmacology
volume
57
issue
1
pages
171 - 179
publisher
American Society for Pharmacology and Experimental Therapeutics
external identifiers
  • scopus:0033976629
ISSN
0026-895X
language
English
LU publication?
no
id
ae8471a1-01e0-4880-afa6-1cd56729ee98
date added to LUP
2017-04-07 10:26:00
date last changed
2017-04-18 13:24:52
@article{ae8471a1-01e0-4880-afa6-1cd56729ee98,
  abstract     = {<p>The aim of this study was to identify the location of the N terminus of peptide agonist ligands when bound to the human B1 bradykinin (BK) receptor. To reach this aim, we exploited the fact that high-affinity binding of kinin peptides to the human B1 receptor subtype requires a peptide N-terminal L- Lys, whereas high-affinity binding to the B2 receptor subtype does not require this residue. This was done by comparing the affinities of BK, a B2 receptor-selective peptide, and kallidin or Lys-BK, a less receptor-selective peptide, for chimeric proteins in which each B1 receptor domain had been substituted in the human B2 receptor and expressed in HEK293 cells. Individual substitution of transmembrane domains 1-7 (TM-I-VlI) and extracellular domains 1-4 (EC-I-IV) of the B1 receptor in the B2 receptor influenced the affinities of BK and Lys-BK approximately equally. In contrast, substitution of B1 EC-IV dramatically reduced the affinity and potency of BK, whereas these parameters for Lys-BK were essentially unaltered. Substitution of either the N- or C-terminal half of B1 EC-IV in the B2 receptor only had a limited effect on the peptide binding constants, indicating the involvement of multiple residues throughout this domain. Complementary mutations of the N-terminal residue in Lys-BK revealed that both the positive charge and the proper spatial orientation of this residue were required for interaction with B1 EC-IV. Thus, the N-terminal residue of peptide agonists when bound to the human B1 receptor is positioned extracellularly and interacts with EC-IV.</p>},
  author       = {Fathy, Dana B. and Kyle, Donald J. and Leeb-Lundberg, Fredrik},
  issn         = {0026-895X},
  language     = {eng},
  number       = {1},
  pages        = {171--179},
  publisher    = {American Society for Pharmacology and Experimental Therapeutics},
  series       = {Molecular Pharmacology},
  title        = {High-affinity binding of peptide agonists to the human B1 bradykinin receptor depends on interaction between the peptide N-terminal L-lysine and the fourth extracellular domain of the receptor},
  volume       = {57},
  year         = {2000},
}