Identification of candidate pheromone receptors from the light brown apple moth (Epiphyas postvittana)

Epiphyas postvittana, or the light brown apple moth (LBAM), is a common horticultural pest that causes damage in many important horticultural crops of Australia, New Zealand and most recently California. Control strategies employed to manage this pest include the use of insecticides, biological control agents and mating disruption. We aim to improve the efficacy of mating disruption using knowledge of the molecular basis of the insect’s sex pheromone reception system.

Expressed sequence tag and genome databases have been established from which we have isolated odorant (OR) and pheromone receptor (PR) genes. Using comparison with known insect ORs and PRs we have identified fifty-two putative receptors from LBAM. Quantitative real-time polymerase chain reaction was used to determine the relative abundance of their transcripts in a range of tissues including male and female antennae. We found at least five transcripts displaying male-biased expression in antennae, which likely indicates a role in the detection of the female-produced sex pheromone. Full-length sequences of LBAM receptors were then generated and used in phylogenetic comparisons with PRs from other moth species. From these analyses candidate PRs were chosen and introduced into cell-based reporter systems to facilitate the characterization of their interactions with LBAM sex pheromone components.