Infection by Grapevine fanleaf nepovirus (GFLV), a bipartite RNA virus of positive polarity belonging to the Comoviridae family, causes extensive cytopathic. The specific transmission of Grapevine fanleaf virus by its nematode vector Xiphinema index is solely determined by the viral coat protein. There are plenty of plant viruses that no one has heard of, but few are as widely known as grapevine fanleaf virus. Learn how to identify a sick.
|Published (Last):||25 July 2014|
|PDF File Size:||5.38 Mb|
|ePub File Size:||19.14 Mb|
|Price:||Free* [*Free Regsitration Required]|
Articles with ‘species’ microformats All stub articles. Unlike VPg labeling, the intracellular coat protein distribution was not homogeneous in between cells.
Fruit quality is affected due to a decrease in sugar content and titratable acidity. In contrast to uninfected cells, in which plastids and mitochondria were found surrounding the nucleus Fig. Effects of site-directed mutagenesis on the presumed fahleaf triad and substrate-binding pocket of grapevine fanleaf nepovirus kDa proteinase. Replication of tobacco mosaic virus on endoplasmic reticulum and role of the cytoskeleton and virus movement protein in intracellular distribution of viral RNA.
Laser scanning was performed by using the multitrack mode to avoid cross talk. Redistribution of Golgi stacks and other organelles during mitosis and cytokinesis in plant cells. The structure and origin of these aggregates could now be resolved in much better detail by CLSM. Inhibition of poliovirus RNA synthesis by brefeldin A.
Grapevine fanleaf virus – Wikipedia
Open in a separate window. To further characterize the GFLV-induced vesicles, crude extracts of healthy and infected T-BY2 protoplasts were fractionated in a linear sucrose gradient.
They were used at a 1: The VPg-containing perinuclear aggregates and punctate dsRNA labeling are indicated in panel N by full arrowheads and in panel O by arrows.
Cellular COPII proteins are involved in production of the vesicles that form the poliovirus replication complex. The sedimentation of Golgi Fig. Small vesicles were specifically immunotrapped by vrus from ER-enriched bottom fractions of the sucrose gradient from infected protoplasts. Panel J is a 2. The coat protein derives from RNA2  and forms the icosahedral capsid of 60 identical protein subunits.
On the contrary, anti-VPg revealed several bands in total Fig. Control experiments were performed with healthy protoplasts treated similarly or by using infected protoplasts incubated in the absence of primary antibodies to verify the specificity of the labeling. Using epifluorescence microscopy, we have previously described the formation of a perinuclear complex where viral RNA was synthesized and viral proteins accumulated 23but this could not be further analyzed due to technical limitations.
Also, the productive life of GFLV-infected vineyards is significantly reduced. It infects grapevinescausing chlorosis of the leaves and lowering the fruit quality.
Grapevine Fanleaf Virus Replication Occurs on Endoplasmic Reticulum-Derived Membranes
Grapevine fanleaf virus symptoms – yellow mosaic pattern on leaf L and bright yellow vein banding on viurs. To compare the distribution of the viral proteins involved in replication with that of proteins involved in movement and encapsidation, we analyzed the intracellular distribution of the movement protein 2B MP and the coat protein 2C CPboth of which are dispensable for replication Photos courtesy of Canadian Food Inspection Agency.
Leaves are severely distorted, asymmetrical, cupped and puckered, and exhibit acute dentations.
Finally, coat protein was also sometimes observed within the nucleoplasm Fig. Effect of viruw on the synthesis of very-long-chain fatty acids in microsomes from leek seedlings. In view of the close resemblance between both systems, we suggest that GFLV could use a similar mechanism to recruit membranes for replication purposes.
Browse related by Tag grapesgrapes disease management. Grapevine fanleaf nepovirus P38 putative movement protein is not transiently expressed and is a stable final maturation product in vivo. Malformations of leaves and canes are usually not prominent, but clusters fanlead be smaller than normal and may have shot berries. Membrane targeting sequences in tombusvirus infections. Staining and observations were as described elsewhere For immunofluorescence microscopy, polyclonal anti-2B antibodies named anti-MP raised in rabbits as described in 53 were used at a 1: The natural host range for GFLV is primarily limited to species of the Vitis genus, so introduction to a new vineyard is likely through plantings of virus-infected nursery stock.
These spots proved to be localized at the tip of MP-labeled tubules Fig. A human virus protein, poliovirus protein 2BC, induces membrane proliferation and blocks the exocytic pathway in the yeast Saccharomyces cerevisiae. Viurs organization of grapevine fanleaf nepovirus RNA2 deduced from the K polyprotein P2 in vitro cleavage products. Michler for technical assistance in electron microscopy. Intracellular localization of poliovirus plus- and minus-strand RNA visualized by strand-specific fluorescent in situ hybridization.
Grapevine Fanleaf Degeneration Disease
Cell viability was assessed on aliquots of protoplasts by adding 0. Image acquisition was performed as previously described A faint background signal due to the anti-VPg antibodies was occasionally found at the cell periphery Fig. In conclusion, both de novo birus of membranes and endomembrane vesicular trafficking are most probably required for GFLV replication. View publishing information about this page. Mock-inoculated and infected protoplasts were harvestedat 24 hpi R to U or 48 hpi A to Q.
However, Golgi stacks were never found in the VPg-labeled aggregates, as judged by the absence of yellow signal in the merged pictures Fig. Sucrose gradient fractionation and analysis. Observations were done under an epifluorescence microscope Nikon Eclipse E with adequate filters. No electron-dense structures similar to those described in CPMV-infected cells 15 were observed.