Structural Basis of Odor Sensing by Insect Heteromeric Odorant Receptors

Overview

Journal Science

Specialty Science

Date 2024 Jun 13

PMID 38870275

Authors

Jiawei Zhao

Andy Q Chen

Jaewook Ryu

Josefina Del Marmol

Affiliations

Soon will be listed here.

Abstract

Most insects, including human-targeting mosquitoes, detect odors through odorant-activated ion channel complexes consisting of a divergent odorant-binding subunit (OR) and a conserved co-receptor subunit (Orco). As a basis for understanding how odorants activate these heteromeric receptors, we report here cryo-electron microscopy structures of two different heteromeric odorant receptor complexes containing ORs from disease-vector mosquitos or . These structures reveal an unexpected stoichiometry of one OR to three Orco subunits. Comparison of structures in odorant-bound and unbound states indicates that odorant binding to the sole OR subunit is sufficient to open the channel pore, suggesting a mechanism of OR activation and a conceptual framework for understanding evolution of insect odorant receptor sensitivity.

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