Insect odorant receptor complex (OR/Orco complex)

Insect heteromeric olfactory receptor complexes are essential components of the insect chemosensory system, typically composed of a variable odorant receptor (OR) subunit and a highly conserved odorant receptor co-receptor (Orco) [6, 16]. These complexes function as ligand-gated non-selective cation channels that convert environmental chemical signals into electrical impulses in olfactory sensory neurons [1, 13]. Because Orco is nearly ubiquitous across insect species and essential for the trafficking and function of all ORs, it has emerged as a primary target for developing novel insect repellents and behavior-modifying compounds [2, 5]. Disrupting these complexes can impair critical behaviors such as host-seeking in disease vectors like mosquitoes, which transmit malaria, Zika, and dengue fever [10, 11]. Pharmacological agents like DEET and VUAA1 interact with these complexes to either inhibit or over-stimulate olfactory signaling, effectively masking human scents or environmental cues [3, 4, 9]. Targeting the conserved Orco subunit offers the potential for broad-spectrum control of agricultural pests and disease-carrying insects [1, 15].

Other names

Insect heteromeric olfactory receptorOrco-dependent odorant receptorOdorant-gated ion channel complexInsect OR/Orco complexOdorant receptor complex

Allosteric modulation or direct gating of the heteromeric ion channel complex formed by a specific odorant receptor (OR) and the Orco co-receptor [1, 12].