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.

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In other projects Wikimedia Commons Wikispecies. The external surface of the vesicles was systematically coated with electron-dense material Fig. Cellular COPII proteins are vrapevine in production of the vesicles that form the poliovirus replication complex.

RNA1 encodes polyprotein P1 kDawhich is processed by an embedded proteinase activity into five proteins required for replication, namely, 1A of unknown function1B probably the helicase1C VPg1D proteinaseand 1E polymerase 38 To demonstrate whether the ER-derived aggregates were involved in viral replication, double-labeling experiments were performed with anti-dsRNA and anti-VPg antibodies.

From Wikipedia, the free encyclopedia. It is associated with membranous structures and is recruited by the RNA1-encoded replication machinery.

Grapevine Fanleaf Degeneration Disease

Immunolabeling of viral proteins. A profound alteration of the cortical network was observed, together with a marked condensation of the ER around the nucleus Fig.

Poor vine health also predisposes vines to winter injury and death in colder climates. In contrast to proteins involved in viral replication, the 2B movement protein and, to a lesser extent, the 2C coat protein were not confined to the viral compartment but were transported toward the cell periphery, a finding consistent with their role in cell-to-cell movement of virus particles. It is transmitted via a nematode vector, Xiphinema index.


The trapping of vesicles was particularly pronounced in fractions 11 to 13, which proved to be highly enriched in vesicles ca. Panels F, J, and U correspond to healthy cells.

They were used at a 1: To further refine the analysis of GFLV replication sites, the ultrastructural organization of the perinuclear aggregates containing the viral products was studied by electron microscopy on infected protoplasts Fig.

Ultrastructural analysis of the GFLV-induced perinuclear compartment.

Grapevine Fanleaf Virus Replication Occurs on Endoplasmic Reticulum-Derived Membranes

Trapevine this case, no immunolabeling corresponding to replication-specific proteins was found to localize with it any more. The specific cytopathological effect of GFLV infection culminated in the nearly complete depletion of the cortical ER accompanied by a progressive build-up of perinuclear virus-induced ER aggregates.

Panels J and K are orthogonal projections of two series of optical sections through a healthy cell with a typical cortical ER J; single arrowheads and an infected cell showing a depletion of the cortical ER K; single arrowheads. In conclusion, both de novo ranleaf of membranes and endomembrane vesicular trafficking are most probably required for GFLV replication. Protein 2A of grapevine fanleaf nepovirus is implicated in RNA2 replication and colocalizes to the replication site.

Protoplasts were further incubated for 48 h and harvested. Such parallelism is not unexpected since CPMV and GFLV belong to the same family and share many common features, among them a similar genome organization 2. fnaleaf


Structural organization of poliovirus RNA replication is mediated by viral proteins of the P2 genomic region. Foliar symptoms develop early in the spring and persist through the vegetative season, although symptoms ranleaf be difficult to find in fully grown canopies later in summer.

For FDA, the parameters were as follows: In spring, affected plants in a vineyard can readily be spotted from a distance.

Grapevine Fanleaf Virus Replication Occurs on Endoplasmic Reticulum-Derived Membranes

Bottom fractions enriched in ER rather than Golgi markers contained also the and kDa VPg precursors and electron microscopy of these fractions revealed the presence of numerous membraneous vesicles. Viral proteins involved in replication were immunodetected on these vesicles in CPMV-infected cells This fanlewf is particularly visible in Fig.

These structures contained VPg either as a final maturation product or more likely as polyprotein precursors involved in RNA replication and could either take the shape of grapsvine ring or a cap or appear multilobed.

Phospholipid biosynthesis and poliovirus genome replication, two coupled phenomena. The sedimentation of Golgi Fig. A monoclonal antibody, JIM84, recognizes the Golgi apparatus and vidus membrane in plant cells. Mock-inoculated and infected protoplasts were harvestedat 24 hpi R to U or 48 hpi A to Q. Effect of cerulenin on the synthesis of very-long-chain fatty acids in microsomes from leek seedlings.

Three tobacco T-BY2 cell lines were used throughout this study: