Insect olfactory neurons: receptors, development, and function.

Insects represent the most diverse group of animals in the world. While the olfactory systems of different species share general principles of organization, they also exhibit a wide range of structural and functional diversity. Scientists have gained tremendous insight into olfactory neural development and function, notably in Drosophila, but also in other insect species (see reviews by Benton, 2022; Robertson, 2019; Yan et al., 2020). In the last few years, new evidence has steadily mounted, for example, the stoichiometry of odorant receptor and co-receptor (OR-Orco) complex. This review aims to highlight the recent progress on four aspects: (1) the structure and function of the OR-Orco complex, (2) chemosensory gene co-expression, (3) diverse neural developmental processes, and (4) the role of genes and neurons in olfactory development and olfactory-mediated behavior.