Cell-based system for identification of olfactory receptors

Abstract

The discovery and characterization of odorant receptors (ORs) beginning in the early 1990s have opened up the ability to study olfaction from a molecular perspective. Hundreds of OR genes that differ between organisms exist, and each gene codes for a G protein coupled receptor (GPCR) that can be activated by a large variety of odorants. Thus, the process of deorphaning, or identifying the cognate ligand(s) for each receptor, is critical for understanding how smells are perceived. This chapter reviews the usage of heterologous systems and associated accessory proteins for expressing ORs in vitro, notably the luciferase assay system for high-throughput OR screening. This in vitro method of characterizing ORs is also compared to ex vivo preparations, with a discussion of advantages and drawbacks of each supported by experimental evidence.