Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 1996 May 31;271(22):12795-800.

Vasoactive intestinal peptide (VIP)1 receptor. Three nonadjacent amino acids are responsible for species selectivity with respect to recognition of peptide histidine isoleucineamide.

Author information

  • 1Unité de Recherche de Neuroendocrinologie et Biologie Cellulaire Digestives, Institut National de la Santé et de la Recherche Médicale, INSERM U410, Faculté de Médecine Xavier Bichat, BP 416, 75870 Paris Cedex 18, France.

Abstract

Vasoactive intestinal peptide (VIP)1 receptors in rats and humans recognize peptide histidine isoleucineamide (PHI) with high and low affinity, respectively. We took advantage of this phenotypic difference to identify the domain responsible for the selective recognition of PHI by rat and human receptors which display >80% sequence identity. After transfection of human and rat receptors in COS cells, the ratio of IC50 for PHI/IC50 for VIP (referred to as P/V) in inhibiting 125I-VIP binding was shown to be >1,000 and <40, respectively. Construction of eight rat/human receptor chimerae by overlap polymerase chain reaction and determination of their P/V ratios demonstrated that the critical domain for PHI recognition is present within a sequence comprising part of the first extracellular loop and third transmembrane domain. This domain contains three different amino acids numbered according to human and rat sequences, respectively, e.g. Gln207 (human) versus His208 (rat), Gly211 versus Ala212 and Met219 versus Val220. Site-directed mutagenesis introducing individual, double, or triple mutations in a chimeric construct revealed that all three amino acids were involved in the recognition of PHI. Triple mutations were then introduced in the wild-type receptors i.e. Q207H, G211A, M219V human VIP1 receptor and H208Q, A212G, V220M rat VIP1 receptor, resulting in a complete change in their phenotype from human to rat and from rat to human, respectively. The results demonstrate that three nonadjacent amino acids are responsible for the selective recognition of PHI by human and rat VIP1 receptors.

PMID:
8662697
[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk