Cellular uptake of peptide nanoparticles in the isolated midgut of Popillia japonica (Newman): Potential for increasing efficacy of RNAi-based pest management strategies

Monday, November 14, 2022

8:00 AM – 8:12 AM PT

Location: Vancouver Convention Centre, Meeting Room 304/305

Presenting Author(s)

Elijah P. Carroll

masters student
Auburn University
Auburn, Alabama

Co-Author(s)

AA

Adriana Avila-Flores

Auburn University
Auburn, Alabama
EM

Erin McGraw

Auburn University
Auburn, Alabama
NK

Nitish Kunte

Auburn University
Auburn, Alabama
DH

David Held

Professor and Department chair
Auburn University
Auburn, Alabama

RNA interference (RNAi) triggered by small interfering RNA (siRNA) has been found to function in most organisms and holds promise as a novel pest management strategy. RNAi techniques have produced efficient and systemic responses in Coleoptera. Degradation of naked siRNA in the environment and within the insect, as well as the localized delivery of siRNA to a specific site in vivo present major challenges to the use of RNAi techniques for pest management strategies. Branched amphiphilic peptide capsules (BAPC’s) can complex with dsRNA and have been used to successfully target genes outside the site of delivery (gut epithelium) via ingestion. This suggests that BAPC’s can protect dsRNA from degradation in the gut environment and successfully shuttle it across gut epithelial cells. In this study, our objectives were to 1) To gain insight regarding the cellular uptake mechanisms and transport of dsRNA-BAPC’s complexes across the midgut of Popillia japonica, and 2) Determine whether feeding on dsRNA and dsRNA-BAPC complexes targeting gut peritrophins of P. japonica would result in the suppression of gut peritrophin synthesis, leading to death.Our results suggest that dsRNA-BAPC’s complex can be transported across the midgut epithelium, and treatment of the tissue with endocytosis inhibitors effectively suppresses intracellular transport. The results of these experiments have implications for using dsRNA-BAPC’s complexes for delivering target specific dsRNA to manage P. japonica.