Expanding the RNAi Toolkit: Host-induced gene silencing of CHITIN SYNTHASE VI via linear double-stranded and paperclip RNA confers plant tolerance to Sclerotinia sclerotiorum

ABSTRACT: Sclerotinia sclerotiorum, the causal agent of white mold, is a devastating fungal pathogen that infects over 600 host plant species. Sclerotinia causes billions of dollars in crop losses, and contemporary control methods rely on broad-spectrum fungicides that may negatively impact the agroecological environment. Thus, there is a direct and immediate need to develop plants that are tolerant to Sclerotinia infection. Accordingly, we developed transgenic Arabidopsis thaliana lines expressing either linear double-stranded (ds) RNA or paperclip (pc) RNA constructs to silence the Sclerotinia CHITIN SYNTHASE VI gene and impart fungal protection across the entire plant lifecycle through host-induced gene silencing (HIGS). Leaf infection assays showed marked reductions in disease severity and target transcript abundance in both ds- and pcRNA-expressing transgenic lines compared to the wild-type control. To investigate the molecular basis of this protection, we performed global dual-RNA sequencing directly at the plant–pathogen interface. In addition to CHITIN SYNTHASE VI silencing, we found enrichment of biological processes involved in cell wall turnover in Sclerotinia infecting both ds- and pcRNA transgenic lines, accompanied by a significant reduction in fungal load at the site of infection. This reduction in pathogen pressure translated into improved plant tolerance, as growth- and photosynthesis-associated pathways were concurrently enriched in both transgenic plant lines. Together, these findings demonstrate that HIGS of chitin synthesis can effectively suppress S. sclerotiorum disease progression and confer plant protection. Finally, the engineering of alternative RNA constructs, such as paperclip RNA, expands the potential of RNAi-based crop protection tools as flexible and sustainable options for disease management against fungal pathogens.

ORGANISM(S): Arabidopsis thaliana Sclerotinia sclerotiorum

PROVIDER: GSE346618 | GEO | 2026/09/14

REPOSITORIES: GEO