Genome-Wide Identification and Expression Pattern of Cytochrome P450 Genes in the Social Aphid Pseudoregma bambucicola

SIMPLE SUMMARY: Differences in P450 gene composition and expression have important implications for the normal growth and development of insects. Pseudoregma bambucicola is a social aphid that produces genetically identical first-instar soldiers and normal nymphs within the colonies. The soldiers have harder epidermis, enlarged forelegs, longer frontal horns, and are sterile. We identified 43 P450 genes in this species and inferred their possible function based on phylogenetic analyses. We identified a number of P450 genes that are expressed at higher levels in soldiers than in normal nymphs and adult aphids, such as CYP18A1, CYP4G332, and CYP4G333. This study provides a basis for further exploring the function of P450 genes in this social insect. ABSTRACT: Cytochrome P450 monooxygenases (P450s) have a variety of functions, including involvement in the metabolism of exogenous substances and the synthesis and degradation of endogenous substances, which are important for the growth and development of insects. Pseudoregma bambucicola is a social aphid that produces genetically identical but morphologically and behaviorally distinct first-instar soldiers and normal nymphs within colonies. In this study, we identified 43 P450 genes based on P. bambucicola genome data. Phylogenetic analysis showed that these genes were classified into 4 clans, 13 families, and 23 subfamilies. The CYP3 and CYP4 clans had a somewhat decreased number of genes. In addition, differential gene expression analysis based on transcriptome data showed that several P450 genes, including CYP18A1, CYP4G332, and CYP4G333, showed higher expression levels in soldiers compared to normal nymphs and adult aphids. These genes may be candidates for causing epidermal hardening and developmental arrest in soldiers. This study provides valuable data and lays the foundation for the study of functions of P450 genes in the social aphid P. bambucicola.