According to the latest news from the Chinese Academy of Agricultural Sciences (hereinafter referred to as the Chinese Academy of Agricultural Sciences), the crop virus disease epidemic and control innovation team of the Institute of Plant Protection (hereinafter referred to as the Institute of Plant Protection) of the Academy of Plant Protection (hereinafter referred to as the Institute of Plant Protection) has found that the southern rice black stripe dwarf virus (SRBSDV) enters the vesicles of the midgut epithelial cells through the interaction of the membrane fusion related proteins of the viral shell protein and the white-backed planthopper family, and fuses to form a large vesicle, and finally breaks through the middle intestine cells to release a large number of virions to achieve efficient virus transmission. The relevant research results were recently published online in Molecular Plant Pathology.
Wang Xifeng, chief of the team and a researcher at the Institute of Plant Protection of the Chinese Academy of Agricultural Sciences, introduced that nearly 70% of plant virus transmission in nature needs to rely on mediator insects. For example, mosquitoes can transmit the dengue virus, mosquitoes are mediator insects. When mediator insects eat the sap of the phloem of plants, plant viruses, especially persistent viruses, will be ingested into the intestines of insects with the sap, enter the hemolymphalym by crossing epithelial cells, and reach the salivary glands with the help of the insect's circulatory system. When fed again, the virus enters healthy plants with saliva. Efficient transmission of virulence by mediator insects is the key to disease outbreaks, and breakthrough in the midgut is the first and most important barrier for viruses to enter the insect body.
The team targeted the southern rice black-striped dwarf virus and the mesosome white-backed planthopper, and electron microscopy observed that many viruses were present in the vesicles of intestinal epithelial cells, while forming a large vesicle that surrounded a large number of viruses near the cell membrane near the side of the blood cavity. The shell protein P10 of the virus was found to interact with the two vesicle-related membrane proteins VAMP7 and Vti1a through interoptimal screening, and the complex containing VAMP7/Vti1a was mainly involved in the material transport of the cells. After the mediator insect is poisoned, the virus and VAMP7 or Vti1a are gradually co-localized in the cell over time and transferred from the cytoplasm to the cell membrane. Interfering with vamp7 or Vti1a expression does not affect the virus entering the intestine and the accumulation in the intestine, but significantly reduces the accumulation of virus in hemolymphalym, while inhibiting the rate of transmission. This suggests that the virus transports and spreads itself by interacting with VAMP7 and Vti1a and using a mediator vesicle transport system.
The study reveals a key mechanism by which plant reoviruses can overcome vector insect midgut escape barriers by hijacking vesicles, providing new insights into the role of vesicle transport in viral transmission, while providing candidate targets for interrupting the spread of viral diseases. (Reporter Qu Jian)
Source: Science and Technology Daily