关键词: 星天牛, 转录组, 高通量测序, 系统发育, 解毒酶蛋白基因

Abstract: [Objective]This study aimed to investigate the transcriptome information and the expression profiles of cytochrome P450 monooxygenase (P450) (CYP), carboxylesterase (CarE) and glutathione S-transferase (GST) detoxification enzymes in Anoplophora chinensis. The phylogenetic tree was constructed to explore the types and phylogenetic relationships of the three enzymatic gene families, and to provide a basis for the study of the adaptability of A. chinensis to multiple host species and the mechanism of insecticide resistance.[Method]The high-throughput sequencing technique, Illumina HiSeq^TM2500, was employed for transcriptome sequencing of A. chinensis, and the data analysis. The phylogenetic analysis of detoxifying enzymes proteins with their homologous protein from close relative species of Coleoptera was conducted.[Result]The clean reads were then de novo assembled into 55 260 unigenes, and 32 247 unigenes were annotated by homologous comparison with public databases. Most unigenes were annotated in the Swiss-Prot database (99.11%), the unigenes of A. chinensis had the highest homology (60.25%) to those of Tribolium castaneum when annotated to Nr database. In the GO database, 8 083 unigenes were successfully annotated and was able to be broadly divided into 3 categories and 47 sub-types, and 4 600 unigenes matched with 162 prediction paths in KEGG database. Using gene annotation, 248 detoxification enzyme genes were found to be expressed in A. chinensis, including 139 CYP genes, 72 CarE genes, and 37 GST genes. Phylogenetic analysis showed that most of the CYP genes of A. chinensis were clustered with at least one of the related species of Coleoptera. In the P450 gene family, the number of CYP6 family was similar to other related species (Coleoptera), and contained the largest number of genes. The CarE detoxification enzyme genes were mainly composed of four types:β-esterase, neurochemotactic protein, exogenous metabolic enzyme and unknown category, and they may be involved in several processes (hormones and pheromones, nerve and developmental processes, digestion and detoxification, respectively). The GST expression mainly consisted of Microsomal GST, Sigma GST, Omega GST, Delta GST, Theta GST subfamilies, which have the function of protecting biomolecules from oxidative damage and catalytic activity.[Conclusion]This study presented the data of transcriptome, and preliminarily analyzed the expression and differentiation profiles of three detoxifying enzymes in A. chinensis, which could provide fundamental information and reference for adaptability to multi-host species, resistance of pesticides, and genetic mechanism of A. chinensis.

Key words: Anoplophora chinensis, transcriptome, high-throughput sequencing technology, phylogeny, detoxifying enzyme gene