Abstract:

Juvenile hormone binding protein (JHBP), a carrier protein binds with juvenile hormone (JH) to form a complex for the transport of juvenile hormone to its target organs and the regulation of growth and development of insects. In this study, 7 juvenile hormone binding protein cDNA sequences were screened in the transcriptome of M. separata, and a highly expressed juvenile hormone binding protein MsJHBP3 (GenBank accession number: MZ577068) when induced by juvenile hormone was obtained. The full length of MsJHBP3 cDNA sequence was 839 bp with an open reading frame (ORF) of 729 bp, encoding 242 amino acids. The isoelectric point and predicted molecular weight were 5.35 and 27.02 kDa, respectively. In different developmental stages, MsJHBP3 was expressed the highest in the pupal stage and the lowest in the second instar larval stage. When the 4th instar larvae were treated with siRNA interference for 6 h, the gene silencing efficiency reached 79.72%, the content of juvenile hormone increased by 1.14 folds, while the pupation rate and the emergence rate significantly decreased by 7.42% and 3.75%, respectively, compared to the control. Transcriptome data analysis showed 212 differentially expressed genes, including 105 up-regulated and 107 down-regulated genes. Among them, juvenile hormone methyltransferase gene, juvenile hormone epoxide hydrolase gene, and juvenile hormone esterase gene were up-regulated. MsJHBP3 was involved in the growth and development and the regulation of JH metabolism. These results provide basic data for the excavation of key genes in the growth and development of M. separata, providing new target gene and pathway for M. separata control.

Key words:

Mythimna separata, juvenile hormone binding protein; RNA interference, real-time PCR, transcriptome