Identification of a TOR signaling pathway gene as a candidate target for reproductive management of Adelphocoris suturalis

Authors: ZHENG, WANYING - Huazhong Agricultural University; JIAO, PANYANG - Huazhong Agricultural University; XU, XIAONA - Huazhong Agricultural University; MA, WEIHUA - Huazhong Agricultural University; Hull, Jimmy; HUA, HONGXIA - Huazhong Agricultural University; CHEN, LIZHEN - Huazhong Agricultural University

Submitted to: Journal of Integrative Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/29/2024
Publication Date: 4/1/2025
Citation: Zheng, W., Jiao, P., Xu, X., Ma, W., Hull, J.J., Hua, H., Chen, L. 2025. Identification of a TOR signaling pathway gene as a candidate target for reproductive management of Adelphocoris suturalis. Journal of Integrative Agriculture. 24(4):1529-1541. https://doi.org/10.1016/j.jia.2024.08.005.
DOI: https://doi.org/10.1016/j.jia.2024.08.005

Interpretive Summary: RNA interference (RNAi) is a post-transcriptional mechanism that promotes degradation of transcripts via uptake of double-stranded RNA (dsRNA) fragments corresponding to the target gene. The high sequence-dependent specificity of this process coupled with its ease of incorporation into diverse delivery systems makes it a promising strategy for agricultural pest control. Successful RNAi-based pest management, however, is dependent on species-specific identification of effective target genes and pathways as target efficacy can vary across taxa. The target of rapamycin (TOR) signaling pathway has been linked to many biological processes, including ovarian development. To assess the potential for this pathway as a target for RNAi-based management of Adelphocoris suturalis, a plant bug pest of many cropping systems, three principal components of the pathway were targeted for RNAi knockdown and effects on ovary development and egg laying were examined. All three impaired oocyte development and reduced the total number of eggs laid. Further, spraying plant bugs with a dsRNA formulation for one of the genes complexed to a nanocarrier compound likewise resulted in reduced egg laying. These results expand our understanding of the processes regulating oocyte development in plant bugs and provide new candidates for RNAi-based A. suturalis management.

Technical Abstract: Adelphocoris suturalis is an agricultural pest of multiple crops that increasingly experiences outbreaks that cause severe economic damage. The development of resistance to traditional control approaches, including non-target resistance to commercial Bacillus thuringiensis (Bt) cotton, have further exacerbated their pest status and amplified the need for more sustainable methods of control. RNA interference (RNAi)-based pest management strategies, such as root soaking and transgenic plants that express dsRNAs, have been shown to be reliable, eco-friendly pest control strategies. To identify new RNAi targets for potential A. suturalis population control, we investigated the target of rapamycin (TOR) signaling pathway. A critical role for this pathway in A. suturalis reproductive regulation was suggested by pharmacological analyses. Subsequent RNAi-mediated knockdown of the A. suturalis TOR pathway genes TOR, Ras homolog enriched in the brain (Rheb), and ribosomal S6 kinase (S6K) reduced fertility. Moreover, a spray-induced and nanocarrier-delivered gene silencing (SI-NDGS) system targeting TOR successfully suppressed ovarian development, which demonstrates its effectiveness as a pest control target. These results provide a critical foundation for understanding reproductive regulation in A. suturalis and introduce new candidates for RNAi-based A. suturalis management.