An insect trypsin-like serine protease as a target of microRNA: Utilization of microRNA mimics and inhibitors by oral feeding

作者：Jayachandran Balachandran; Hussain Mazhar; Asgari Sassan^*

来源：Insect Biochemistry and Molecular Biology, 2013, 43(4): 398-406.

DOI：10.1016/j.ibmb.2012.10.004

• MicroRNA
• Mimic
• Inhibitor
• Trypsin-like serine protease

MicroRNAs (miRNAs) are non-coding small RNAs (18-25 nt) that play crucial roles in various biological processes, including development, as gene regulators. In this study, we identified a miRNA, har-miR-2002b, that is specifically expressed during larval stages of Helicoverpa armigera (cotton bollworm). For the first time, we explored the possibility of utilizing synthetic inhibitor and mimic of a miRNA by oral feeding and confirmed that the inhibitor and mimic can successfully inhibit/oversupply har-miR-2002b in H. armigera larvae. Bioassays by oral feeding indicated 70% reduction in fecundity and 40% larval mortality in the presence of har-miR-2002b mimic. In addition, a large proportion of those larvae that made it to the pupal stage were deformed and only few moths emerged from them. This implied an important role of har-miR-2002b in larval development and adult fecundity. A trypsin-like serine protease (Ha-UP) was identified as a target of har-miR-2002b. In vivo and in vitro studies revealed that in the presence of the miRNA mimic Ha-UP transcript/protein levels and enzyme activity were significantly reduced. In contrast, inhibition of har-miR-2002b led to significant up-regulation of Ha-TLP transcript levels. This is the first study which shows the potential of utilization of miRNA mimics and inhibitors in pest control by targeting specific insect genes.

• 出版日期2013-4