Identification of cytochrome P450, odorant-binding protein, and chemosensory protein genes involved in Type II sex pheromone biosynthesis and transportation in the tea pest, Scopula subpunctaria.

Sex pheromone-based pest management technology has been widely used to monitor and control insect pests in the agricultural, forestry, and public health sectors. Scopula subpunctaria is a widespread tea pest in China with Type II sex pheromone components. However, limited information is available on the biosynthesis and transportation of Type II sex pheromone components. In this study, we constructed an S. subpunctaria sex pheromone gland (PG) transcriptome and obtained 85,246 transcripts. Cytochrome P450 monooxygenases (CYPs) thought to epoxidize dienes and trienes to epoxides in the PG and odorant-binding proteins (OBPs) and chemosensory genes (CSPs) thought to be responsible for the binding and transportation of sex pheromone components. In present study, a total of 79 CYPs, 29 OBPs and 17 CSPs were identified. We found that SsubCYP341A and SsubCYP341B_ortholog1 belonged to the CYP341 family and were more highly expressed in the PG than in the female body. Of these, SsubCYP341A was the seventh-most PG-enriched CYP in the PG transcriptome. Two CYP4 members, CYP340BD_ortholog2 and CYP4G, were the top two most PG-enriched CYPs. Tissue expression and phylogenetic tree analysis showed that SsubOBP25, 27, and 28 belonged to the moth pheromone-binding protein family; they were distinctly expressed in the antennae and were more abundant in male antennae than in female antennae. SsubCSP16 was distributed into the same clade as CSPs from other moths that showed high binding affinities to sex pheromone components. It indicated that all the above-mentioned genes could be involved in sex pheromone biosynthesis or transportation. Our study provides large-scale PG sequence information that can be used to identify potential targets for the biological control of S. subpunctaria by disrupting its sex pheromone biosynthesis and transportation pathways.