Development of Modular Geminivirus-Based Vectors for High Cargo Expression and Gene Targeting in Plants

Area of Science:

• Plant molecular biology
• Virology
• Biotechnology

Background:

• Viral vectors are crucial for gene editing and protein expression in plants.
• Optimizing viral vector design for specific applications remains challenging.
• Understanding how viral components affect gene expression and replication is limited.

Purpose of the Study:

• To design a modular viral vector system based on the geminivirus beet curly top virus (BCTV).
• To compare different viral vector architectures for improved cargo expression and replicon accumulation.
• To establish design principles for future geminivirus-based vectors.

Main Methods:

• Developed a GoldenBraid (GB)-compatible BCTV-based viral vector system.
• Employed a modular cloning strategy for diverse reporter constructs.
• Compared native BCTV promoters against the constitutive 35S promoter.
• Assessed the impact of removing BCTV virion-sense genes on expression and accumulation.

Main Results:

• Native BCTV promoters showed superior performance compared to the 35S promoter.
• Deletion of BCTV virion-sense genes enhanced reporter gene expression.
• These modifications did not influence overall replicon accumulation.
• The modular BCTV vectors proved effective for protein expression and gene targeting.

Conclusions:

• The new modular BCTV vectors facilitate protein expression and gene targeting in plants.
• Identified key design principles for optimizing geminivirus-based viral vectors.
• The system is expected to promote wider adoption of replicon-based strategies in plant biotechnology.