title: Distinct olfactory signaling mechanisms in the malaria vector mosquito Anopheles gambiae.
abstract: Anopheles gambiae is the principal Afrotropical vector for human malaria, in which olfaction mediates a wide range of both adult and larval behaviors. Indeed, mosquitoes depend on the ability to respond to chemical cues for feeding, host preference, and mate location/selection. Building upon previous work that has characterized a large family of An. gambiae odorant receptors (AgORs), we now use behavioral analyses and gene silencing to examine directly the role of AgORs, as well as a newly identified family of candidate chemosensory genes, the An. gambiae variant ionotropic receptors (AgIRs), in the larval olfactory system. Our results validate previous studies that directly implicate specific AgORs in behavioral responses to DEET as well as other odorants and reveal the existence of at least two distinct olfactory signaling pathways that are active in An. gambiae. One system depends directly on AgORs; the other is AgOR-independent and requires the expression and activity of AgIRs. In addition to clarifying the mechanistic basis for olfaction in this system, these advances may ultimately enhance the development of vector control strategies, targeting olfactory pathways in mosquitoes to reduce the catastrophic effects of malaria and other mosquito-borne diseases.
authors.affiliation: Department of Biological Sciences and Pharmacology, Center for Molecular Neuroscience, Institutes of Chemical Biology and Global Health, Vanderbilt University, Nashville, Tennessee, United States of America.
authors.forename: Chao
authors.initials: C
authors.lastname: Liu
authors.forename: R Jason
authors.initials: RJ
authors.lastname: Pitts
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Bohbot
authors.forename: Patrick L
authors.initials: PL
authors.lastname: Jones
authors.forename: Guirong
authors.initials: G
authors.lastname: Wang
authors.forename: Laurence J
authors.initials: LJ
authors.lastname: Zwiebel
mesh_terms: D000818:Animals; D000852:Anopheles / Q000502:physiology*; D001522:Behavior, Animal / Q000187:drug effects; D003671:DEET / Q000494:pharmacology; D020868:Gene Silencing; D007302:Insect Repellents / Q000494:pharmacology; D007303:Insect Vectors / Q000502:physiology*; D007814:Larva / Q000502:physiology; D008288:Malaria / Q000469:parasitology / Q000635:transmission; D009833:Olfactory Pathways / Q000502:physiology; D034622:RNA Interference; D018035:Receptors, Odorant / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D012903:Smell / Q000502:physiology*
chemical_list: D007302:Insect Repellents; D018035:Receptors, Odorant; D003671:DEET
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