Advances in the Structural Elucidation, Mechanistic Understanding, and Applications of Insect Odorant Receptors

doi:10.16409/j.cnki.2095-039x.2026.05.004

Abstract

Abstract: Insect odorant receptors (ORs) are core molecular determinants of volatile chemical signal detection in the peripheral olfactory system, playing pivotal roles in host localization, mate recognition, oviposition-site selection, and ecological adaptation. Early studies, through gene identification, expression profiling, electrophysiological characterization, and mutagenesis analyses, established the classical model in which ORs and the odorant receptor co-receptor (Orco) together form a functional ion channel complex. In recent years, advances in cryo-electron microscopy and protein structure prediction have enabled the successive resolution of Orco homotetrameric, OR homotetrameric, and OR-Orco heterotetrameric structures, substantially deepening our understanding of their assembly modes, ligand recognition, and gating mechanisms. This review systematically summarizes the discovery of insect ORs, the classical functional model, the process of structural elucidation, investigations into activation mechanisms, and their applications in evolutionary ecology, virtual screening, and biosensor development, while also highlighting future prospects for interdisciplinary applications.

Key words: insect, odorant receptor, three-dimensional structure, ligand recognition mechanism, interdisciplinary applications

CLC Number:

S476

ZHANG Yutong, YANG Yujie, WANG Xiaoqing, WANG Guirong, LIU Yang. Advances in the Structural Elucidation, Mechanistic Understanding, and Applications of Insect Odorant Receptors[J]. Chinese Journal of Biological Control, 2026, 42(2): 305-316.

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