Abstract

The ambrosia beetle Euwallacea interjectus is a polyphagous pest native to eastern Asia that has recently caused significant damage to poplar plantations in China. This study identified and characterized cytochrome P450 (CYP) genes from E. interjectus through molecular cloning and phylogenetic analysis. These genes were classified into three major clans: mitochondrial, CYP3, and CYP4, demonstrating high sequence conservation and evolutionary kinship with CYP families from other bark beetles, particularly within the Euwallacea and Dendroctonus genera. Expression profiling across various developmental stages via qRT-PCR revealed distinct stage-specific regulation patterns. Most CYP genes showed elevated expression during larval and pupal stages, with notable upregulation of genes such as CYP302A1 and CYP301A1 during metamorphosis. In adults, reproductive females exhibited increased expression of multiple CYP genes associated with detoxification and physiological maturation, while males showed elevated expression of specific CYPs in late pupal and adult stages. These expression dynamics reflect the functional diversification of CYP genes in supporting development, reproduction, and ecological adaptation in E. interjectus . This study provides the first comprehensive molecular characterization of CYP genes in this species, offering valuable insights into their roles in growth and development and establishing a foundation for further research into their biological functions.