Improvement of Rice Seed Storability by Regulating Lipid Metabolism Using a CRISPR/Cas9 System

Area of Science:

• Agricultural Science
• Biotechnology
• Plant Science

Background:

• Long-term rice grain storage is vital for global food security but challenged by inherent susceptibility to deterioration.
• Rice seed degradation during storage is linked to lipid metabolism and reactive oxygen species (ROS) accumulation.

Purpose of the Study:

• To enhance rice seed storability by genetically modifying key lipid metabolism enzyme genes using CRISPR/Cas9 technology.
• To elucidate the molecular mechanisms underlying seed deterioration and improved storability through untargeted lipidomics.

Main Methods:

• CRISPR/Cas9 gene editing was employed to create a fad2-1/lox3/pldα1 triple mutant in the Yu-Zhen-Xiang (YZX) rice cultivar.
• Untargeted lipidomic analysis was performed to investigate changes in lipid profiles and metabolic pathways.
• Accelerated aging tests were conducted to evaluate grain quality and nutritional value of the modified rice lines.

Main Results:

• The Yu-Zhen-Xiang (YZX) cultivar exhibited inferior seed storability compared to Xi-Li-Gong-Mi (XLGM) due to accelerated lipid catabolism and ROS overproduction.
• The fad2-1/lox3/pldα1 triple mutant (flp mutant) displayed reduced fatty acid accumulation and lower ROS content.
• Lipidomic data revealed that decreased lipid hydrolysis and peroxidation contributed to the enhanced storability of the flp mutant.

Conclusions:

• Targeting lipid metabolism genes via CRISPR/Cas9 offers a robust strategy for rapidly improving rice aging tolerance.
• The study provides insights into the mechanisms of rice seed deterioration, paving the way for enhanced grain storage solutions.
• The developed approach holds potential for application in other cereal crops to address critical grain storage challenges.