Abstract: 【Aim】The aim of this study is to identify antimicrobial peptide Drosomycin gene in Shelfordella lateralis, and examine the developmental and tissue expression properties and the expression of antimicrobial peptide Drosomycin gene induced by bacteria and insecticide. 【Methods】Drosomycin gene of S. lateralis was identified based on the transcriptome data of S. lateralis and further validated through RT-PCR. The expression levels of the Drosomycin gene in S. lateralis at different developmental stages (1st instar nymph, 4th instar nymph, and the 6-day-old female and male adults), in different tissues (head, thorax, gut, leg, fat body, hemolymph and integument) of the 4th instar nymphs, and in the 4th instar nymphs after injection of Escherichia coli, Staphylococcus aureus, and deltamethrin (1×10^-5 mg/L) were assayed by using RT-qPCR. 【Results】The cDNA sequence of Drosomycin gene SlDros (GenBank accession no.: PQ464795) of S. lateralis was cloned. The open reading frame of SlDros was 201 bp in length encoding 66 amino acids. SlDros was highly expressed in the 6-day-old male adults. SlDros was mainly expressed in the head, integument, thorax and hemolymph of the 4th instar nymphs. The expression levels of SlDros in the 4th instar nymphs at 12, 24 and 48 h after injection of E. coli, and those at 6, 12, 24 and 72 h after injection of S. aureus were significantly increased as compared with those of the control group injected with distilled water. At 96 h post-injection of deltamethrin, the expression level of SlDros in the 4th instar nymphs was significantly higher than that of the control group injected with acetone. 【Conclusion】The antimicrobial peptide Drosomycin gene is present in S. lateralis, and stress of bacteria or insecticide can induce its expression. These results provide a foundation for studying the function of antimicrobial peptides in S. lateralis and the further development of new antimicrobial drugs.

Key words: Shelfordella lateralis, antimicrobial peptide, drosomycin, gene expression, deltamethrin, bacteria