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Structural basis of odor sensing by insect heteromeric odorant receptors.

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 Aedes aegypti or Anopheles gambiae. 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.

SUBMITTER: Zhao J

PROVIDER: S-EPMC11235583 | biostudies-literature | 2024 Jun

REPOSITORIES: biostudies-literature

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Structural basis of odor sensing by insect heteromeric odorant receptors.

Zhao Jiawei J Chen Andy Q AQ Ryu Jaewook J Del Mármol Josefina J

Science (New York, N.Y.) 20240613 6703

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 <i>Aedes aegypti</i> or <i>Anopheles gambiae</i>. These ...[more]

PMID: 38870275

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