Odorant receptor co-receptor (Orco) (Orco)

The Odorant receptor co-receptor (Orco) is a highly conserved transmembrane protein that is essential for the function of the insect olfactory system. Unlike mammalian olfactory receptors, which are G protein-coupled receptors, insect odorant receptors (ORs) form heteromeric complexes with Orco to function as ligand-gated ion channels (Nature, 2013; Science, 2008). Orco serves as a universal chaperone and co-receptor for all specific odor-tuning ORs, making it the primary molecular target for common insect repellents such as N,N-Diethyl-meta-toluamide (DEET). By modulating Orco activity, these substances can either mask attractive host odors (e.g., carbon dioxide, sweat) or directly trigger aversive neural pathways, effectively preventing disease vectors like mosquitoes from locating and biting human hosts (Nature, 2019). Consequently, Orco is a critical target for pharmacological intervention to reduce the transmission of vector-borne infectious diseases, including malaria, dengue, and Zika virus (PNAS, 2014). Research in this field focuses on identifying novel Orco agonists and antagonists to develop more effective, long-lasting, and environmentally safe spatial repellents.

Other names

Olfactory receptor co-receptorOR co-receptorOR7OR83bDOR83b83b

Allosteric modulation of odorant receptor complexes and direct activation of aversive olfactory receptor neurons