Pine bark beetles can thrive beneath the bark of host trees, where the environment is poisonous to most other insects, because they have enzymes that can alter pine resin toxins into less dangerous chemicals. These "resin detoxification" reactions are thought to have evolved, in some cases, into pheromone biosynthetic reactions. Bark beetles rely on aggregation pheromones -chemicals that they release into the atmosphere that are perceived by other bark beetles- in order to coordinate colonization of new host trees. The pheromones and resin detoxification products are chemically similar monoterpenoids. Pheromone production and resin detoxification both require cytochrome P450 enzymes to chemically alter monoterpenoid structures.
The researchers will investigate the P450 enzymes involved in these two processes. They will use a combination of molecular cloning, enzyme assays, and computer modeling of P450 enzymes that modify monoterpenes in order to compare how the P450s are used and have evolved in different bark beetle species. These comparisons will allow scientists to begin to understand the evolutionary pressures at work on the beetle-host interaction. This work will contribute to long term efforts to manage destructive pine bark beetles by providing data that will guide development of pheromone-based control measures, and by identifying new, species-specific molecular targets for future management strategies.This project provides opportunities for graduate and undergraduate students to gain expertise in biochemistry, molecular biology, and molecular modeling. The researchers have a proven commitment to including members of under-represented groups in their research teams, and will continue to do so. Some of the enzymes characterized in this study may be useful as biotechnological tools to produce and/or modify monoterpenes in the food/cosmetics industries.
