In a breakthrough that could transform how crops deal with rising temperatures and infections, scientists at Kolkata’s Bose Institute, an autonomous institute of the Department of Science and Technology (DST), have developed a smart molecular tool that helps plants defend themselves, only when needed. This innovation, based on a modified version of the CRISPR gene-editing system, could pave the way for more resilient food crops like tomatoes, potatoes and tobacco.
Published in the International Journal of Biological Macromolecules, the research led by Prof. Pallob Kundu used a modified version of CRISPR known as dCas9. Unlike regular CRISPR tools that cut DNA, dCas9 doesn’t slice the genetic code, it works like a switch that turns specific genes on or off. What makes this system even smarter is that it activates only when the plant is under stress.
To make the system responsive, scientists used a small segment of a natural tomato protein called NACMTF3. This segment, known as the TM domain, acts like a lock, keeping the dCas9 switch outside the cell's nucleus. But when stress, such as heat, hits the plant, the lock is released, and the switch enters the nucleus to trigger the plant’s defense genes.
Tested in tomatoes, potatoes and tobacco, the tool showed impressive results. In tomatoes attacked by the heat-loving bacterial pathogen Pseudomonas syringae, the system activated two key immune genes, CBP60g and SARD1, right when the plant needed them. This timely response helped the tomatoes fight off the disease, even during heatwaves.
The tool also proved effective in helping plants manage heat stress. By switching on two “heat helper” genes, NAC2 and HSFA6b, during high temperatures, it helped tomato plants stay green, hold on to water and remain healthy despite the heat.
The research offers hope to farmers struggling with unpredictable weather and climate challenges. The system is energy-efficient, as it remains inactive until triggered by stress, and could be used in other important crops like eggplants and chilies in the future.
