Recently, the Institute of Crop Science of the Chinese Academy of Agricultural Sciences revealed a new mechanism by which viruses hijack the rapesinolide pathway to inhibit jasmonate-mediated resistance to rice stripe disease, providing a theoretical basis for the breeding of rice stripe disease resistant varieties through molecular design.

Rice stripe disease is a viral disease transmitted by grey planthopper, once the disease can not be treated, so it is called "rice cancer". The cultivation of resistant varieties is the most economical and effective way to control rice stripe disease. The team used the established large-scale rice stripe disease resistance identification technology system in the early stage to clone the first rice stripe disease resistance gene STV11, and created a molecular marker polymerization breeding technology system, which effectively solved the problem of stripe disease in japonica rice areas in southern China. However, the molecular mechanism of rice stripe virus interaction with rice remains unknown.

The team found that increasing the exogenous or endogenous steroids and jasmonic acid and enhancing the signaling pathways of the two hormones could significantly improve the resistance of rice to striped blight.On the contrary, when the signal of rapeseed steroid or jasmonic acid is blocked, rice is more susceptible to disease. Further studies showed that rice infected with xERoba virus could significantly inhibit the synthesis of endogenous brassinosteroids in plants, thus increasing the accumulation of OsGSK2, a key negative regulator of its signaling pathway. Experiments confirmed that OsGSK2 can interact with the key positive regulators of the jasmonic acid pathway and degrade it through phosphorylation, thus reducing the brassinosteroid-enhanced resistance to fringe blight, indicating that brassinosteroid-mediated resistance to fringe blight is dependent on the JASmonic acid pathway. These studies revealed the molecular mechanism by which the virus ACTS on the steroid pathway to inhibit jasmonic-acid-mediated bacterial blight resistance, deepened people's understanding of the interaction between the virus and its host, and proposed a new strategy for breeding resistant varieties by using molecular breeding technology.

Time: 2020.09.03

Source: http://caas.cn/xwzx/tpxw/307360.html