Enhancing virus-mediated genome editing for cultivated tomato through low temperature

Area of Science:

• Plant Science
• Molecular Biology
• Agricultural Biotechnology

Background:

• CRISPR/Cas gene editing offers precise genetic modification for crop improvement.
• Developing efficient genome-editing tools is crucial for applying these technologies in plant breeding.
• Virus-induced genome editing (VIGE) presents a promising avenue for crop genetic enhancement.

Purpose of the Study:

• To enhance the virus-induced genome editing (VIGE) system in cultivated tomato (S. lycopersicum).
• To investigate the effect of low temperatures on VIGE efficiency using viral vectors.
• To develop a method for producing heritable, virus-free gene-edited tomato lines.

Main Methods:

• Utilized tobacco rattle virus (TRV) and potato virus X (PVX) vectors to deliver CRISPR/Cas components targeting the SlPDS gene.
• Introduced mobile RNA sequences (tFT or tRNA^Ileu) to enhance editing efficiency.
• Applied low-temperature treatments during viral infection and subsequent tissue culture stages.

Main Results:

• Low temperatures significantly increased viral vector-mediated gene editing efficiency in tomato tissues.
• Tissue culture combined with low-temperature incubation at the initiation stage yielded high mutation rates (>70%) in the SlPDS gene.
• Successfully obtained heritable, virus-free gene-edited tomato progenies.

Conclusions:

• Viral vector-mediated gene editing in tomato is significantly enhanced by low temperatures.
• The improved VIGE system facilitates higher mutation rates and the production of desirable gene-edited traits.
• This study provides a practical approach for accelerating the development of gene-edited tomato varieties for breeding programs.