The Food and Agriculture Organization of the United Nations estimates that between 20 and 40 percent of global crop production is lost each year to plant pests and pathogenic microbial infections.
According to the paper, scientists found their first clue in tomatoes, which contain a class of proteins that behave differently from those found in the immune systems of other plants.
Most plants have two lines of immune defense – one on the surface of their cells and another inside them, dominated by a disease-resistance protein called NLR.
These proteins, encoded by disease resistance genes, recognize specific invading pathogens and flood the immune system, triggering an efficient and rapid response, helping the plant fight off its enemies.
Usually, the proteins are tightly regulated and present at relatively low levels. But in the heat of battle, when the immune response is activated, it can trigger a “suicide” mechanism that leads to cell death and inhibits plant growth.
However, the researchers found that tomatoes had a class of proteins from the same family that did not seem to follow this pattern.
According to Chai and his colleagues, levels of this protein – called NRC – remain high regardless of whether the plant is under attack, potentially causing an overreaction of the immune system and even cell suicide.
Researchers analyzed the structure of tomato proteins and found that they remain stable by assembling into different forms with the help of a small organic molecule that is involved in the plant’s energy metabolism process.
Cao Yu, a researcher working in the same lab as Chai, said the identification of the mechanism, including the helper, “has important implications” by providing a new theoretical basis for crop breeding and pest control.
The research could open up new agricultural biotechnologies to improve disease resistance in crops without interfering with their normal growth and yield by inducing an exaggerated immune response, he said.
Scientists have long known that plants, like animals, are equipped with an immune system, with the cloning of the first plant disease resistance gene providing molecular evidence in 1994. But the biochemical functions of plant NLR proteins remained elusive. poorly understood.
Shi, who was a junior assistant professor in Princeton University’s molecular biology department, accepted Chai as his first postdoctoral fellow in 1999.
Last year, in an interview with The Economic Observer in China, Shi described his former student as “one of the leading scientists in the world” in his field.
Upon his return to China in 2004, Chai joined the National Institute of Biological Sciences in Beijing as an independent principal investigator, focusing his research on the field of plant immunology at that time.
Last August, Chai and his long-time collaborator Zhou Jianmin won China’s prestigious Future Science Prize for their pioneering contributions to the understanding of immune mechanisms in plants.
Zhou, a researcher at the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences, and Chai shared the $1 million prize, initiated in 2016 by a group of scientists and entrepreneurs to promote basic scientific research in China.
The privately funded award recognizes outstanding scientists in three main fields – life sciences, physical sciences and mathematics and computer science.