Receptor Accessory Protein 4 (REEP4)

Transport of G protein-coupled receptors (GPCRs) to the cell surface membrane is critical for receptor-ligand recognition. However, mammalian GPCR odorant receptors (ORs), when heterologously expressed in cells, are poorly expressed on the cell surface. By screening for genes that induced cell surface expression of ORs expressed in human embryonic kidney cells, Saito et al. (2004) identified mouse and human REEP1. They searched databases for homologs of REEP1 and identified several other REEP genes, including REEP4. In situ hybridization of mouse olfactory epithelium revealed that, unlike Reep1, Reep4 was not expressed in olfactory neurons. The International Radiation Hybrid Mapping Consortium mapped the REEP4 gene to chromosome 8.