Molecular determinants of odorant receptor function in insects
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The olfactory system of Drosophila melanogaster provides a powerful model to study molecular and cellular mechanisms underlying function of a sensory system. In the 1970s Siddiqi and colleagues pioneered the application of genetics to olfactory research and isolated several mutant Drosophila with odorant-specific defects in olfactory behaviour, suggesting that odorants are detected differentially by the olfactory system. Since then basic principles of olfactory system function and development have emerged using Drosophila as a model. Nearly four decades later we can add computational methods to further our understanding of how specific odorants are detected by receptors. Using a comparative approach we identify two categories of short amino acid sequence motifs: ones that are conserved family-wide predominantly in the C-terminal half of most receptors, and ones that are present in receptors that detect a specific odorant, 4-methylphenol, found predominantly in the N-terminal half. The odorant-specific sequence motifs are predictors of phenol detection in Anopheles gambiae and other insects, suggesting they are likely to participate in odorant binding. Conversely, the family-wide motifs are expected to participate in shared functions across all receptors and a mutation in the most conserved motif leads to a reduction in odor response. These findings lay a foundation for investigating functional domains within odorant receptors that can lead to a molecular understanding of odor detection.
KeywordsDrosophila motifs odor receptor olfaction
- Bohbot J, Pitts RJ, Kwon, HW, Rutzler M, Robertson HM and Zwiebel LJ 2007 Molecular characterization of the Aedes aegypti odorant receptor gene family. Insect Mol. Biol. 16 525–537Google Scholar
- Wanner KW, Anderson AR, Trowell SC, Theilmann DA, Robertson HM and Newcomb RD 2007 Female-biased expression of odourant receptor genes in the adult antennae of the silkworm, Bombyx mori. Insect Mol. Biol. 16 107–119Google Scholar