Characterization of the RDC1 gene which encodes the canine homolog of a proposed human VIP receptor. Expression does not correlate with an increase in VIP binding sites

FEBS Lett. 1992 Mar 30;300(2):149-52. doi: 10.1016/0014-5793(92)80184-i.

Abstract

We have isolated a portion of the canine gene encoding the orphan receptor RDC1 [1]. The complete coding sequence is contained in a single exon, and an intron divides the 5' untranslated region of RDC1 mRNA. The RDC1 protein is 94% homologous to the gene product of GPRN1, which has been proposed to serve as a VIP receptor when expressed in CHO-K1 and COS-7 cells (Sreedharan, S.P. et al. (1991) Proc. Natl. Acad. Sci. USA 88, 4986-4990). Northern analysis indicates that CHO-K1 cells endogenously express a 2.1 kb RDC1 mRNA. However, while CHO-K1 cells possess detectable low affinity [125I]VIP binding sites, VIP binding is not altered in membranes of CHO-K1 cells expressing varying amounts of the RDC1 gene construct. Further, endogenous VIP binding is not increased by transient expression of RDC1 in COS-7 cells. Taken together, the data suggest that RDC1 is not a canine homolog of the proposed VIP receptor.

MeSH terms

  • Animals
  • Base Sequence
  • Blotting, Northern
  • CHO Cells
  • Cell Line
  • Cloning, Molecular
  • Cricetinae
  • Dogs
  • GTP-Binding Proteins / metabolism
  • Humans
  • Molecular Sequence Data
  • RNA / isolation & purification
  • Receptors, Gastrointestinal Hormone / genetics*
  • Receptors, Gastrointestinal Hormone / metabolism
  • Receptors, Vasoactive Intestinal Peptide
  • Sequence Homology, Nucleic Acid
  • Transfection
  • Vasoactive Intestinal Peptide*

Substances

  • Receptors, Gastrointestinal Hormone
  • Receptors, Vasoactive Intestinal Peptide
  • Vasoactive Intestinal Peptide
  • RNA
  • GTP-Binding Proteins