New dimensions in the molecular genetics of insect chemoreception.

Chemoreception is the foundation of olfaction and taste, which in insects underlie the detection of humans to whom they spread disease and crops that they ravage. Recent advances have provided clear and in some cases surprising new insights into the molecular genetics of chemoreception. We describe mechanisms that govern the choice of a single Odorant receptor gene by an olfactory receptor neuron in Drosophila. We highlight genetic and epigenetic mechanisms by which chemoreceptor expression can be modulated. Exitrons, RNA editing, and pseudo-pseudogenes in chemosensory systems are described. We summarize key insights from the recent structural determinations of odorant and taste receptors. Finally, new molecular components of chemosensory systems, including long noncoding RNAs, are described.