Comparative Transcriptome Analysis Of Monochamus Alternatus (Coleoptera:Cerambycidae) With And Without Pine Wood Nematode Bursaphelenchus Xylophilus

The main purpose of this study was to establish a transcriptome database of Monochamus alternatus adult tissues with and without Bursaphelenchus xylophilus,to reveal the transcriptome expression characteristics of Monochamus alternatus responding to Bursaphelenchus xylophilus.The transcriptomes of trachea epidermis,and fat body of M.alternatus adults were sequenced using the Illumina Hi Seq TM 2000 platform,and the transcriptome data was denovo assembled using Trinity software,and gene annotation was conducted by using the NCBI database.In this paper,we analyzed the differentially expressed genes of adult of alternatus alternatus with and without pine wood nematode by DEG-Seq,enriched the up-regulated genes by go and KEGG metabolic pathway,and verified the expression level of genes related to stress response,antimicrobial peptide and melanization in humoral immunity by real-time quantitative PCR.After sequencing and filtering,a total of 55 059 unigenes were obtained with an average length of 1 536 bp.A total of 24 354 unigenes were annotated using BLASTX searches against the databases,of which 4 022 unigenes were assigned in GO database and 6 098 unigenes were assigned in KEGG database.The enrichment analysis of GO and KEGG showed that the main differentially expressed genes in trachea of M.alternatus adults carrying B.xylophilus are related with pressure regulation,tissue and DNA repair,and hormone response.The results of real-time quantitative PCR analysis showed that the expression levels of genes related to stress were at The trachea of Monochamus alternatus carrying Bursaphelenchus xylophilus was significantly up-regulated compared to the trachea of Monochamus alternatus without carrying Bursaphelenchus xylophilus,while the antibacterial peptides and genes related to melanization reaction in humoral immunity showed a general downward trend.This study preliminarily clarified the gene expression model of stress-related genes up-regulated by Monochamus alternatus carrying Bursaphelenchus xylophilus and the related negotiable response-related genes as a whole showed a downward trend.Response process,in-depth study of the mechanism that Monochamus alternatus can carry pine wood nematode,laid the foundation,provides a new reference direction for the prevention and control of pine wood nematode disease.