Characterization of P450 monooxygenase gene family in the cotton aphid, Aphis gossypii Glover

Abstract

• A total of 49 CYP sequences were classified into 13 families and 21 subfamilies. • 47 genes were found to be functional and P450-encoding genes are conserved in gene structure and organization in cotton aphids. • The cotton aphid P450 family has evolutionary differentiation. • The distribution across the genome and phylogenetic clustering analysis indicated past occurrence of gene duplication events. Cytochrome P450 monooxygenases play an important role in the biosynthesis and detoxification of endogenous compounds. In this study, we analyzed a number of P450 genes through transcriptome-wide and genome analyses in Aphis gossypii Glover, the most notorious cotton pests. A total of 49 CYP-putative sequences were identified and classified into 13 families and 21 subfamilies. We identified a putative P450 motif (FXXGXXXCXG), and further analyzed other conserved sequences, which indicate that forty-seven of the forty-nine genes seem to be functional, but one is likely non-functional and one is predicted pseudogenes. We found that P450-encoding genes are conserved in gene structure and organization (number, position, and phase of introns) in cotton aphids. The size, transcription orientation, and comparison with other insects of the cotton aphid P450 family suggested that it has evolutionary differentiation. The distribution across the genome and phylogenetic clustering analysis indicated past occurrence of gene duplication events. These results may provide valuable clues for understanding the evolution of the aphid genome, studying the functions of P450s in cotton aphid, and further selecting candidate genes for novel insect control methods.