Recently, the Crop Disease Team of Nanjing Agricultural University and the Shanghai Plant Adversity Center of the Chinese Academy of Sciences Xing Weiman Group (currently working at Shanghai Normal University) and the Institute of Genetics of the Chinese Academy of Sciences Xie Qi The researcher jointly published a research paper entitled”Phytophthora sojaeeffector Avr1d functions as an E2 competitor and inhibits ubiquitination activity of GmPUB13 to facilitate infection” in the Proceedings of the National Academy of Sciences”PNAS”. As a molecular probe, a new protein GmPUB13 involved in immune response was identified, and the composite crystal structure of the U-box domain of Avr1d and GmPUB13 was analyzed for the first time, revealing that pathogens interfere with plant immunity through secretion effectors and GmPUB13 interactions. The new mechanism has broadened the understanding of the interaction process of host microorganisms and provided a theoretical basis for the improvement of crop resistance traits.
Due to the high multiple cropping index and the common repeated cropping, soybean root rot is widespread and harmful in my country. It is the main restricting factor affecting the high and stable production of soybeans in my country. Soybean disease Mold is one of the main pathogens causing root rot. In the process of host infection, the effector is the key weapon for pathogens to attack the host’s immune system. Therefore, the effector is also an important molecular probe to explain the mechanism of plant immunity to pathogens. Ubiquitination is a common post-transcriptional modification. In recent years, many studies have shown that ubiquitination is involved in plant growth and immune processes. Many pathogenic bacteria and oomycete effectors have been found to target the host U-box E3 ubiquitin ligase, indicating that the targeted plant U-box E3 ubiquitin ligase is a common way for pathogens to attack the plant immune system. The mechanism of action. However, the mechanism of effector targeting E3 ubiquitin ligase is still unclear.
PsAvr1d is a non-toxic effector of Phytophthora sojae identified by Professor Wang Yuanchao’s team. The mutation of this effector can lead to the loss of the soybean disease resistance gene Rps1d. Resistance (Yin, et al., MPMI, 2013). In this study, the team found that in the absence of host soybean disease resistance genes, Avr1d can promote Phytophthora infection. Yeast screening library and biochemical experiments proved that Avr1d interacts with soybean U-box E3 ubiquitin ligase GmPUB13. By analyzing the composite crystal structure of the U-box domain of Avr1d and GmPUB13, it is found that Avr1d can occupy the U-box domain of GmPUB13. Among them, the 90th phenylalanine (F) on Avr1d is necessary for Avr1d to target GmPUB13 and exert its toxic function. Further biochemical experiments proved that Avr1d inhibits the ubiquitin ligase activity of GmPUB13 and stabilizes the GmPUB13 protein by competing for the U-box between E2 ubiquitin-conjugating enzyme and GmPUB13, thereby promoting the infection of Phytophthora sojae. This study demonstrated from a new perspective how the pathogenic effector Avr1d”strikes” the host immune-related protein GmPUB13 with small gains and precision. It provides new theoretical knowledge for understanding the molecular mechanism of soybean resistance to pathogens, and also provides new theoretical knowledge for understanding the molecular mechanism of soybean resistance to pathogens. Modifying the immune system of crops provides important molecular targets.
Dr. Lin Yichun from Nanjing Agricultural University and Dr. Hu Qinzhu from Shanghai Center for Plant Adversity are the co-first authors, Professor Wang Yuanchao and Professor Xing Weiman are the co-corresponding authors, and Professor Xie Qi, Chinese Academy of Sciences Professor Brett M. Tyler from Oregon State University, Associate Professor Wang Yan and Associate Professor Ye Wenwu from Nanjing Agricultural University also participated in this research work. The research was supported by the National Soybean Industry Technology System, the National Natural Science Foundation of China, and the Ministry of Agriculture and Rural Affairs Key Research and Development Program. support.