Cloning of a human heptahelical receptor closely related to the P2Y5 receptor

Biochem Biophys Res Commun. 1997 Jul 9;236(1):106-12. doi: 10.1006/bbrc.1997.6895.


The 6H1 receptor cloned from activated chicken T cells was initially considered an orphan G-coupled receptor, but was later included in the P2Y family of receptors for purine and pyrimidine nucleotides on the basis of a significant amino acid identity and was renamed P2Y5. Analysis of the expressed sequence tag database revealed the presence of a related sequence exhibiting 63% amino acid identity with this receptor. Starting from this partial sequence, we have isolated a complete clone and identified a 1113 base pair open reading frame encoding a new G-coupled receptor that we have called P2Y5-like. This sequence exhibits 61% identity with the chicken P2Y5 sequence and 30-33% with other P2Y subtypes. A construct encoding this P2Y5-like receptor was transfected into COS-7, 1321N1, and CHO-K1 cells, and expression was documented by Northern blotting. None of the 40 nucleotides and nucleosides tested was able to elicit a response in any of four functional assays: inositol phosphate formation, stimulation or inhibition of cAMP formation, and extracellular acidification measured with a microphysiometer. These results suggest either that the natural ligand of the P2Y5-like receptor is an uncommon nucleotide or alternatively that despite its structural similarity to the P2Y family it is not a nucleotide receptor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • COS Cells
  • Chickens
  • Cloning, Molecular
  • Humans
  • Molecular Sequence Data
  • Protein Folding
  • Receptors, Cell Surface / genetics*
  • Receptors, Cytoplasmic and Nuclear / genetics
  • Receptors, G-Protein-Coupled*
  • Receptors, Purinergic P2 / genetics*
  • Sequence Alignment
  • Signal Transduction


  • LPAR4 protein, human
  • Receptors, Cell Surface
  • Receptors, Cytoplasmic and Nuclear
  • Receptors, G-Protein-Coupled
  • Receptors, Purinergic P2

Associated data

  • GENBANK/AF005419