The cytochrome P450 gene family of <i>Aedes albopictus</i> : Insights from comparative genomics and developmental transcriptomics

Aedes albopictus, the most invasive mosquito species worldwide, constitutes a significant public health threat. The cytochrome P450 (CYP450) genes in insects, which are associated with growth, development, and metabolism of both endogenous and exogenous substances, have attracted considerable attention. However, the role of CYP450 gene family in Ae. albopictus mosquito development remains largely unexplored. Here, a comprehensive analysis of CYP450 genes in mosquitoes, using comparative genomics combined with Illumina short-read and PacBio full-length RNA sequencing, was conducted to characterize Ae. albopictus CYP450 genes. As a result, CYPomes of 24 mosquito species were identified, including 174 CYP450 transcripts in Ae. albopictus genome and 124 isoforms in full length transcriptome, respectively. These CYP450 genes were categorized into four CYP clans containing 14 families, exhibiting a power-law distribution pattern. Ecological traits, such as pathogen type and blood source were speculated to be related to CYP450 gene family expansion across mosquito species. Gene gains and losses were considered to be the important evolution drivers for shaping the current mosquito CYP450 repertoire. Almost all the CYP450 genes in Ae. albopictus showed developmental dynamic expression patterns. Additionally, PacBio full-length RNA sequencing revealed the complexity of CYPomes, with alternative splice events, APAs and gene fusion events identified in Ae. albopictus CYP450 full length isoforms. Together, this study characterizes the mosquito CYPomes and their evolution history, and reveals the expression dynamics and possible functions of CYP450 gene family in the growth, development, and adaptive strategies of Ae. albopictus.