Polymeric nanoparticle-delivered antisense DNA for soybean weed control

Overview

This technology addresses a critical challenge in soybean agriculture by offering a molecular approach to controlling two of the most problematic weeds: Conyza spp (horseweed) and Digitaria insularis (sourgrass). The solution leverages polymeric nanoparticles—specifically zein and chitosan—as delivery vehicles for antisense DNA oligonucleotides. These oligos are designed to silence genes responsible for synthesizing proteins involved in the primary metabolism of target weeds, effectively disrupting their growth through post-transcriptional gene silencing.

The approach is grounded in prior work demonstrating efficient delivery of antisense DNA to microalgae (Chlamydomonas reinhardtii) using functionalized nanoparticles, achieving a 4-fold reduction in gene expression. Given the physiological similarities between microalgae and weeds when exposed to photosystem II-affecting herbicides, the technology is well-positioned for agricultural weed management applications.

Technical specifications

Core mechanism:

• Antisense DNA oligonucleotides target mRNA encoding proteins essential to weed primary metabolism
• Post-transcriptional silencing occurs through mRNA cleavage, disrupting protein synthesis in target weeds
• Nanoparticle delivery protects oligos and enables controlled release inside plant cells

Delivery system:

• Polymeric nanoparticles composed of zein (a corn-derived protein) and chitosan (a natural polysaccharide)
• Particle size range of 150–250 nm, optimized for plant cell uptake
• Release mechanism utilizes the proton sponge effect, enabling oligonucleotide release in the plant cytoplasm

Validation approach:

• RT-qPCR analysis to confirm gene silencing efficacy
• Agronomic variable assessment to measure weed control outcomes
• Molecular analysis capabilities supported by partner laboratories for plant manipulation and nanoparticle synthesis

Technology readiness level

The technology is currently at an early-to-mid development stage. Prior proof-of-concept work in C. reinhardtii demonstrated successful gene silencing using nanoparticle-delivered DNA oligos, with significant 4-fold decreases in target gene expression within two hours of release. Future validation will focus on synthesizing target-specific antisense oligos for weed primary metabolism genes and evaluating them in controlled plant studies over an estimated one-year development timeline. The research team has access to molecular analysis equipment and partner laboratories with expertise in plant manipulation and nanoparticle synthesis, supporting progression toward field-ready applications.