Abstract: 【Aim】 To establish the transcriptome database of the spotted flesh fly, Wohlfahrtia magnifica, and to explore its genetic data, so as to provide a foundation for further studying the bactrian vaginal fly plague. 【Methods】 The transcriptomes of the larva, pupa and adult of W. magnifica were sequenced by a high-throughput sequencing platform (Illumina Hiseq^TM4000) and subjected to bioinformatics analysis. Olfaction-related genes were screened by differential gene expression analysis and GO function significant enrichment analysis based on the transcriptome data of the larva, pupa and adult of W. magnifica. The expression levels of three olfaction-related genes (OBP99b, OBP56a and OBP99a) in the larva, pupa and adult of W.magnifica were verified by qPCR. 【Results】 The results showed that each sample of W. magnifica generated the transcriptome data of above 4.96 Gb, in which the G+C content was above 35.35%, and the Q20 content was above 97%. A total of 73 303 unigenes could be annotated in NCBI_nr, GO, KEGG, Pfam, Swiss-Prot and eggNOG databases. Among them, the largest number of unigenes (35 066) were annotated in the eggNOG database, and involved in 23 protein functions, among which the unigenes involved in the translation modification and protein turnover accounted for a larger proportion. A total of 29 193 unigenes were annotated in the GO database, and involved in 50 branches of molecular function, cellular component and biological process, with a higher proportion of unigenes involved in biological process and oxidation-reduction process. There were 15 068 unigenes annotated in the KEGG database, with higher proportion of unigenes involved in the signal transduction process. The above data indicated that the transcriptome sequencing result was good, laying a foundation for the follow-up experiment. Based on the transcriptome data of the larva, pupa and adult of W. magnifica, 30 olfaction-related genes including 9 odor-binding protein (OBP) genes were screened. Further gene annotation revealed that OBP99b, OBP56a, and OBP99a showed differential expression (|log₂FC|>1, P<0.05) in different developmental stages of W. magnifica, which was verified by the results of fluorescence quantitative PCR. 【Conclusion】 In this study, the transcriptome data of larva, pupa and adult of W. magnifica were obtained, the olfaction-related genes at different developmental stages of W. magnifica were screened, and the differential expression of OBP99b, OBP56a and OBP99a in the three developmental stages of larva, pupa and adult of W. magnifica was verified. These results provide a new idea for preventing and treating the vaginosis of the bactrian alpaca.

Key words: Wohlfahrtia magnifica, transcriptome, high-throughput sequencing, bioinformatics analysis, fluorescence quantitative PCR