D3047: Utilizing RNA microspheres to improve the RNAi efficiency in the diamondback moth, Plutella xyllostella

Monday, November 11, 2024

9:00 AM – 5:00 PM MST

Location: Phoenix Convention Center, Exhibit Hall 6, PCC

Presenting Author(s)

Rachel Leigh Johnson

Graduate Research Assistant
Kansas State University
Manhattan, Kansas

Co-Author(s)

AN

Amie Elizabeth Norton

Nano entomologist
Kansas State University
Manhattan, Kansas
Kun Yan Zhu

University Distinguished Professor
Kansas State University
Manhattan, Kansas

RNA interference (RNAi) has been widely recognized as a new strategy for insect pest management. However, there are many challenges to the application of this technology in pest management. One challenge is the variability of RNAi efficiency across insect orders due to several factors such as degradation and poor cellular uptake of interfering RNA molecules. RNA microspheres (RMS) are formed from long strands of RNA containing multiple hairpin RNA unit repeats, and their complex structures could be utilized to improve the RNAi efficiency in RNAi-unsusceptible insects such as Lepidopterans. Previously, RMS were shown to improve the cellular uptake in a Lepidopteran cell line and improve gene suppression and larval mortality in feeding based RNAi bioassay; however, more work is needed to characterize the RMS, improve the yield of RMS synthesis, and apply this technology to other species. In this study, we synthesized RMS targeting two genes encoding chitin synthase 1 (CHS1) involved in chitin biosynthesis and chitinase 10 (CHT10) involved in chitin degradation in the diamondback moth, Plutella xylostella. We characterized the RMS and compared the RNAi efficiency of RMS and naked double-stranded RNA (dsRNA) in larvae by using the leaf disc bioassay method. This new technology could be used to formulate more efficient RNAi-based pesticides for the control of Lepidopteran pests.