RNA virus-mediated gene editing for tomato trait breeding

Area of Science:

• Plant biotechnology
• Molecular biology
• Genetics

Background:

• CRISPR-Cas systems enable precise genome editing in various organisms.
• Viral vectors offer efficient delivery of genetic material into plant cells.
• Tomato is a major horticultural crop with significant economic importance.

Purpose of the Study:

• To develop and demonstrate a virus-induced genome editing (VIGE) approach for tomato using an RNA viral vector.
• To assess the efficiency of VIGE for generating mutations in key tomato genes.
• To evaluate the heritability of VIGE-induced mutations for crop improvement.

Main Methods:

• Utilized a potato virus X (PVX)-based RNA viral vector for delivering CRISPR-Cas components.
• Generated Cas9-expressing tomato lines for VIGE experiments.
• Performed VIGE targeting the PHYTOENE DESATURASE (PDS) and STAYGREEN 1 (SGR1) genes.
• Regenerated edited tomato plants from somatic tissues and analyzed progeny for mutations and phenotypes.

Main Results:

• Achieved efficient somatic editing in tomato with indel frequencies up to 58% via VIGE.
• Generated loss-of-function pds mutants exhibiting an albino phenotype.
• Created sgr1 mutants with altered fruit color (red-brown) and high chlorophyll content.
• Confirmed that VIGE-induced mutations were heritable, demonstrating successful trait breeding.

Conclusions:

• VIGE using PVX-based RNA vectors is a viable and efficient method for tomato genome editing.
• This approach facilitates rapid functional genomics studies and the development of novel tomato traits.
• VIGE holds significant potential for precision breeding in tomato and other horticultural crops.