Synthetic Plant Episome Platform for Non-Integrative Multigene Engineering

Overview

This technology offers a novel approach to plant genetic engineering through synthetic plant episomes (synplasomes), which are autonomous, self-replicating DNA constructs that function independently of the host plant genome. Inspired by mitotically stable mammalian episomal architectures and natural eukaryotic extrachromosomal circular DNA (eccDNA) mechanisms, the platform enables sustained multigene expression without integration-associated risks such as insertional mutagenesis.

The synplasome platform addresses key limitations of conventional plant engineering tools, including CRISPR systems, transposons, and R2 retroelements, which depend on Agrobacterium-mediated delivery and carry narrow host range constraints. By mimicking naturally occurring eccDNA architectures, the platform supports cargo capacities exceeding 25 kb, enabling large-payload trait stacking for complex agronomic traits. Delivery is achieved through biocompatible carbon dot (CD) nanomaterial carriers designed to traverse rigid plant cell walls.

Technical specifications

Core technology:

• Patent-pending synthetic episome (synplasome) engineered for autonomous replication and vertical transmission across mitotic cycles
• Non-integrative design eliminates insertional mutagenesis and preserves genomic integrity
• Cargo capacity exceeding 25 kb for multigene construct expression
• Biocompatible carbon dot nanomaterial delivery system enabling whole-seed transformation
• EccDNA-inspired architecture supporting reliable mitotic stability

Validation status:

• Wheat prototype demonstrates successful seedling delivery, expression, and root retention
• Planned validation includes a 5-gene fungal bioluminescence pathway to confirm functional expression
• Optimization targets soybean and Brassica napus seed transformation
• Vertical transmission tracking across multiple vegetative mitotic cycles

Planned development phases:

• Episome architecture assembly and bacterial host stability confirmation
• CD carrier formulation and cell wall barrier optimization
• Real-time bioluminescence validation of non-integrative pathway expression

Technology readiness level

The synplasome platform has demonstrated proof-of-concept delivery and expression in a wheat prototype, confirming seedling delivery, gene expression, and root retention of the episomal construct. The technology is advancing through expanded validation in key commercial crops, with ongoing work to optimize carbon dot carrier parameters for whole-seed transformation in soybean and canola. Functional validation using bioluminescent reporter pathways is underway to confirm sustained, non-integrative expression and vertical transmission across multiple cell generations. The platform is positioned for collaborative development toward broader crop applications and commercial readiness.