Bacterially expressed dsRNA protects maize against SCMV infection

Area of Science:

• Plant Pathology
• Molecular Biology
• Biotechnology

Background:

• RNA interference (RNAi) is a natural plant defense mechanism for sequence-specific gene silencing.
• Posttranscriptional gene silencing (PTGS) relies on double-stranded RNA (dsRNA) homologous to target genes.
• Developing efficient methods for dsRNA production is crucial for agricultural applications.

Purpose of the Study:

• To establish an efficient bacterial system for producing dsRNA against Sugarcane Mosaic Virus (SCMV).
• To evaluate the efficacy of dsRNA application as a preventative measure against SCMV infection in plants.
• To compare the effectiveness of dsRNA derived from different regions of the SCMV coat protein gene.

Main Methods:

• Two SCMV coat protein (CP) gene fragments (CP1 and CP2) were amplified via RT-PCR.
• Fragments were cloned into the pUCCRNAi vector for inverted-repeat dsRNA synthesis.
• Recombinant plasmids were expressed in E. coli HT115, inducing dsRNA production with IPTG.

Main Results:

• Bacterial extracts containing dsRNA were successfully produced and applied as a foliar spray.
• Spraying crude dsRNA extracts demonstrated preventative efficacy against SCMV infection.
• dsRNA derived from the upstream SCMV CP gene region (CP1) showed higher efficacy than the downstream region (CP2).

Conclusions:

• An efficient bacterial expression system for dsRNA production was developed.
• dsRNA application via spraying is a viable strategy for plant viral disease control.
• Targeting specific gene regions can optimize the effectiveness of dsRNA-based plant protection.