Boston, MA — Researchers at the Institute for Plant-Human Interface (IPHI) at Northeastern University, in collaboration with scientists from multiple institutions, have deciphered the molecular mechanism behind a crucial plant defense system, potentially opening new avenues for protecting crops from pathogens. The groundbreaking study, published today in Nature Communications, reveals how plants in the Brassicaceae family (which includes cabbage, canola, and mustard) produce salicylic acid—a key immune hormone that helps plants fight off diseases.
“Understanding how plants naturally defend themselves against pathogens is crucial for developing more resilient crops,” says Dr. Jing-Ke Weng, the study’s senior author and Director of IPHI. “What we’ve discovered is essentially a molecular switch that accelerates the production of a plant’s natural immune response.”
The research team focused on an enzyme called EPS1, which is unique to the Brassicaceae family. This enzyme acts as a catalyst, speeding up the production of salicylic acid when plants encounter pathogens. Using a combination of advanced techniques, including X-ray crystallography and computer simulations, the scientists were able to capture detailed images of the enzyme’s structure and understand exactly how it works.
“What makes this discovery particularly exciting is that we’ve not only understood how this defense mechanism works, but we’ve also shown that we can transfer it to other plants,” explains Dr. Michael Torrens-Spence, one of the study’s lead authors. “When we introduced the EPS1 gene into soybeans, which naturally lack this enzyme, the plants showed enhanced salicylic acid production.”
The implications of this research extend far beyond the laboratory. With global food security increasingly threatened by plant diseases and changing climate conditions, developing crops with enhanced natural immunity could reduce reliance on chemical pesticides and help ensure more stable food production.
In their experiments, transgenic soybeans expressing the EPS1 gene showed up to five times higher levels of salicylic acid compared to regular soybeans. This demonstrates the potential for engineering enhanced disease resistance in important crop species that don’t naturally possess this efficient defense mechanism.
“This work provides a new tool for plant breeders and biotechnologists,” says Dr. Weng. “By understanding and harnessing this natural defense mechanism, we might be able to develop more resilient varieties of important crops without relying on external chemical inputs.”
The study represents a collaboration between scientists at Northeastern University, Massachusetts Institute of Technology, and the Chinese University of Hong Kong. The research was supported by grants from the Pew Scholar Program, the Searle Scholars Program, the Keck Foundation, the National Science Foundation, and the Hong Kong research grants council.
Citation
Torrens-Spence MP, Matos JO, Li T, Kastner DW, Kim CY, Wang Z, Glinkerman CM, Sherk J, Kulik HJ, Wang Y, Weng JK. (2024) Mechanistic basis for the emergence of EPS1 as a catalyst in plant salicylic acid biosynthesis of Brassicaceae. Nat Commun. 15:10356.
News source: IPHI