# Multiple amino acid changes are responsible for the shift of tuning breadth along the evolutionary trajectory of a moth pheromone receptor

## TL;DR

The study shows that multiple amino acid changes in a moth pheromone receptor caused a shift in its sensitivity during evolution.

## Contribution

The study confirms that eight amino acid substitutions are responsible for the evolutionary shift in receptor specificity.

## Key findings

- Eight amino acid substitutions recapitulate the evolution of a moth pheromone receptor's tuning breadth.
- Multiple amino acid changes explain the shift in tuning breadth of Spodoptera OR5 during evolution.
- Results were confirmed using expression in Drosophila olfactory neurons.

## Abstract

Sex pheromone recognition is essential for mating in many insects and plays a major role in maintaining reproductive barriers. A previous study from our lab reported the evolutionary history of the pheromone receptor OR5 in
Spodoptera
moths. Using heterologous expression in
Xenopus
oocytes and site-directed mutagenesis, we found that eight amino acid substitutions were sufficient to recapitulate the evolution from an ancestral broadly-tuned to a highly specific receptor. Here, we confirmed this result using expression in
Drosophila
olfactory neurons. This further confirmed that multiple amino acid changes explain the shift in tuning breadth of
Spodoptera
OR5 during evolution.