Newly discovered plant "disease-resistant small body": reveals the core molecular mechanisms of disease-resistant protein control and activation.

Plants have a complex, well-regulated immune system that identifies pathogenic microorganisms and activates defensive responses to protect themselves from harm.
a large number of disease-resistant proteins in plant cells, is a sentinel that monitors the invasion of disease, and is also the commander of the mobilization plant defense system.
disease-resistant proteins have been discovered for more than two decades, but it is still unclear how they work.
a recent joint study by the team of Chai Jijie of Tsinghua University, Zhou Jianmin of the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences and Wang Hongwei of Tsinghua University, has made important breakthroughs in the field of plant immunity research.
team discovered disease-resistant small body consisting of disease-resistant proteins and analyzed its electromirror structure, thus revealing the core molecular mechanisms of disease-resistant protein control and activation, providing new possibilities for better use of disease-resistant proteins.
results were published on 5 April in two long articles, in the international academic journal Science (Science, Wang et al., 2019a, b).
Science magazine published a review of the results in a commentary by Jeffery Dangl and Jonathan Jones, the world's leading scientists for plant disease research, entitled High Five: a pentangular plant inflammasome. One of the great bottlenecks in the study of disease-resistant protein theory in
is the lack of protein structure.
this is the main direction of Chai Jijie's team since 2004.
disease-resistant protein composition is complex, molecular weight is large, the conformation is variable, which brings great difficulties to the analysis of its structure.
Since the first international identification of disease-resistant proteins 25 years ago, several of the world's top laboratories have failed to purify full-length disease-resistant proteins for structural analysis.
Chai Jijie's team has made a breakthrough in the study of animal inflammatory small body structure in recent years (Hu et al., 2015; Yang et al., 2017).
Because of the similarity between the proteins of the inflammatory small body and the disease-resistant proteins of plants, these studies have accumulated valuable experience for the analysis of the disease-resistant protein structure of plants.
Zhou Jianmin and Chai Jijie team worked together as early as 2007-2008 to present a "bait model" of attack and defense between plants and pathogenic bacteria and provided preliminary evidence (Xing et al., 2007, et Xiang al., 2008; Zhou and Chai, 2008).
Zhou Jianmin's team found several molecular evidences supporting the "bait model" (Zhang et al., 2010; Feng et al., 2012; Wang et al., 2015), and in two jobs in 2012 and 2015, found an amazing attack strategy between pathogens and plants. AvrAC, a pathogenic protein
pathogen bacteria, precisely destroys key components in the plant's immune system, helping bacteria infect plant hosts, while plants use special "bait" proteins to sense AvrAC activity and transmit information to plant disease-resistant protein ZAR1, quickly activating the immune response and removing bacteria.
the cooperation between the two teams for many years, the theory and experimental system formed after long-term accumulation, has laid a solid foundation for further cooperation in the later stages.
Wang's team has long been committed to the research, improvement and improvement of cryoscopic electroscopy, and the reconstruction of high-resolution cryoscopes of proteins has always been the focus and expertise of the team, which provides a strong technical support for the analysis of disease-resistant protein structure.
on the basis of the above-mentioned research, the three teams further cooperated to study the plant disease-resistant protein structure with AvrAC and ZAR1 as the system.
after years of collaborative efforts, successfully assembled a compound containing the activation of ZAR1 (disease-resistant small body, resistosome).
structural studies found that after ZAR1 was activated by AvrAC, it was assembled into a ring-like pentapolymer protein machine containing a total of 15 sub-bases to form disease-resistant small bodies (Figure 1).
through the analysis of the structure and function of the resting state complex, the analysis of disease-resistant proteins from the resting state, through the intermediate state, and finally formed the biochemical process of disease-resistant small body.
team closely combined with structural, biochemical and functional research, revealed the mechanism of disease-resistant small body.
, for example, the formation of disease-resistant small cells directly on the cytoplasm membrane to issue suicide instructions, most likely plant cell death and immune practitioners.
work fills a 25-year gap in the perception of disease-fighting proteins and provides a model for the study of other disease-resistant proteins.
study also found that the assembly, structure and function of plant disease-resistant small organisms are strikingly similar to those of inflammatory cells in animal immunity, demonstrating the power of evolution to immune formation in different life forms.
reviewed in the journal Science in the same paper, Jeffery Dangl and Jonathan Jones, the world's leading scientists for plant disease resistance, spoke highly of the results: "The discovery of the first disease-resistant small body provides clues to how plants control cell death and immunity."
the Journal of Botany also published an internationally renowned plant disease expert Xin Li (Li Wei) and others entitled "Opening the door of defense: plant disease-resistant small body", the results "completed the plant NLR protein complex assembly, structure and functional analysis, revealed the key molecular mechanism of NLR action, is a milestone event in plant immunity research."
a variety of crop pests and diseases, seriously threatening agricultural production.
in order to reduce losses, agricultural production had to be heavily applied chemical pesticides, but this in turn posed challenges to the environment, human health and sustainable agricultural development.
while protecting crops and reducing the use of chemical pesticides has become a difficult problem for agricultural producers and scientists.
the key to solving this problem is the presence of a large number of disease-resistant proteins in plant cells.
these proteins are found to be bacteria, quickly start plant defense response, killing germs, thereby protecting the plant from damage.
the use of disease-resistant proteins, the development of new pest control means, is expected to greatly reduce the application of chemical pesticides.
the analysis of the high resolution structure and mechanism of disease-resistant proteins will lay a core theoretical foundation for the design of new disease-resistant proteins that are broad-spectrum and lasting, and to develop green agriculture.
, Wang Jiyuan, a postdoctoral researcher at Tsinghua University and a visiting researcher at the National Key Laboratory of Plant Genomics at the Institute of Genetic Development, Wang Jia, a postdoctoral fellow of Tsinghua University, and Hu Meixuan, a doctoral student at the National Key Laboratory of Plant Genomics of the Institute of Genetic Development, are co-authors of one of the papers (Wang et al., 2019a);
Chai Jijie, Zhou Jianmin and Wang Hongwei are co-authors of the two papers.
the research was supported by the Class B pilot special "Guided prevention and control of crop pests and diseases - interbiological information flow and behavior manipulation" and the National Nature Fund Innovation Group Project "The Mechanism of Plant Response To Biological Stress".
papers: Wang J, Wang J,, Hu M?, Qi J, Wu S, Wang G, Han Z, Qi Y, Gao N, Wang HW? Ligand-triggered allosteric aDP release primes a plant NLR complex. Science, vol: pagesWang J, Hu M, Wang J, Qi J, Han Z, Wang G, Qi Y, Wang HW? Reconstitution and structure of the plant NLR resistosome conferring immunity. Science, vol:pages Source: Institute of Genetics and Developmental Biology.