Rational engineering approaches for establishing insect olfaction reporters in yeast

Insect olfaction directly impacts insect behavior and thus is an important consideration in the development of smart farming tools and in integrated pest management strategies. Insect olfactory receptors (ORs) have been traditionally studied using Drosophila empty neuron systems or with expression and functionalization in HEK293 cells or Xenopus laevis oocytes. Recently, the yeast Saccharomyces cerevisiae (S. cerevisiae) has emerged as a promising chassis for the functional expression of heterologous seven transmembrane receptors. S. cerevisiae provides a platform for the cheap and high throughput study of these receptors and potential deorphanization. In this study, we explore the foundations of a scalable yeast-based platform for the functional expression of insect olfactory receptors by employing a genetically encoded calcium sensor for quantitative evaluation of fluorescence and optimized experimental parameters for enhanced functionality. While the co-receptor of insect olfactory receptors remains non-functional in our yeast-based system, we thoroughly evaluated various experimental variables and identified future research directions for establishing an OR platform in S. cerevisiae.