Membrane Targeting Sequences in Tombusvirus Infections

Rubino, Luisa; Russo, Marcello

doi:10.1006/viro.1998.9490

Cited by 80 publications

(96 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nevertheless, we show here for the first time that AltMV TGB3 is involved in transport between different cell types adjunct to replication. This distinction between AltMV and PVX may be compared with differences between distinct tombusviruses targeting either mitochondria or peroxisomes to form multivesicular bodies (Rubino & Russo, 1998), similar to the chloroplast vesiculation observed with AltMV TGB3 overexpression.…”

Section: Discussionmentioning

confidence: 87%

Mutation of a chloroplast-targeting signal in Alternanthera mosaic virus TGB3 impairs cell-to-cell movement and eliminates long-distance virus movement

Lim¹,

Vaira²,

Bae

et al. 2010

Journal of General Virology

View full text Add to dashboard Cite

Cell-to-cell movement of potexviruses requires coordinated action of the coat protein and triple gene block (TGB) proteins. The structural properties of Alternanthera mosaic virus (AltMV) TGB3 were examined by methods differentiating between signal peptides and transmembrane domains, and its subcellular localization was studied by Agrobacterium-mediated transient expression and confocal microscopy. Unlike potato virus X (PVX) TGB3, AltMV TGB3 was not associated with the endoplasmic reticulum, and accumulated preferentially in mesophyll cells. Deletion and sitespecific mutagenesis revealed an internal signal VL(17,18) of TGB3 essential for chloroplast localization, and either deletion of the TGB3 start codon or alteration of the chloroplastlocalization signal limited cell-to-cell movement to the epidermis, yielding a virus that was unable to move into the mesophyll layer. Overexpression of AltMV TGB3 from either AltMV or PVX infectious clones resulted in veinal necrosis and vesiculation at the chloroplast membrane, a cytopathology not observed in wild-type infections. The distinctive mesophyll and chloroplast localization of AltMV TGB3 highlights the critical role played by mesophyll targeting in virus longdistance movement within plants.

show abstract

Section: Discussionmentioning

confidence: 87%

Mutation of a chloroplast-targeting signal in Alternanthera mosaic virus TGB3 impairs cell-to-cell movement and eliminates long-distance virus movement

Lim¹,

Vaira²,

Bae

et al. 2010

Journal of General Virology

View full text Add to dashboard Cite

show abstract

“…Deletion of each of the five genes in this group inhibited the accumulation of DI-72 RNA (Table 1). It is possible that the lack of these genes affected membrane composition used by TBSV for replication, i.e., peroxisomal membrane in both plants (30) and yeast (T.P. and P.D.N., unpublished data).…”

Section: Identification Of 96 Yeast Genes Affecting Accumulation Of Tbsvmentioning

confidence: 99%

Yeast genome-wide screen reveals dissimilar sets of host genes affecting replication of RNA viruses

Panavas

Servienė

Brasher

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

200

270

View full text Add to dashboard Cite

host factors ͉ plus-stranded RNA virus ͉ tomato bushy stunt tombusvirus ͉ virus replication ͉ yeast-knockout strains T he success of viruses as pathogens of humans, animals, and plants depends on the viruses' ability to reprogram the host-cell metabolism to support the infection. The virus-host interaction is more complex than the term ''reprogramming'' suggests because host cells have antiviral defense mechanisms. Identifying host genes that can affect virus replication and the infection process is central to understanding the complex role of the host in viral infections. The largest group of viruses, the positive-strand RNA viruses, which include the severe acute respiratory syndrome (SARS) coronavirus and hepatitis C and West Nile viruses, has virion RNAs that are directly translated in the infected cell. Synthesized viral proteins and recruited host proteins mediate processes that lead to efficient multiplication of the viral RNA (1, 2). RNA viruses are important not only as infectious agents but also as tools in biotechnology and gene therapy for expressing selected proteins in cells (3)(4)(5).Yeast is a model eukaryotic cell that has been used extensively to study the roles of individual genes in cellular processes based on genome-wide screens (6-9). Many screens have been based on the yeast single-gene-knockout (YKO) library, because the role of each nonessential yeast gene can be tested for selected functions (10). We and others have developed systems for inducing yeast cells to support the replication of certain positive-strand RNA viruses or their surrogates (11)(12)(13)(14). Here, we apply our previously developed system for robust replication of a small RNA replicon of the tomato bushy stunt virus (TBSV) in yeast (13,15) to screen the entire YKO library for genes influencing the efficiency of viral replication. A total of 96 YKO strains were identified. The identified host genes are either involved in many cellular processes, including nucleic acid, protein, and lipid metabolism, protein targeting͞transport, and general and stress metabolism or have unknown functions. Our results show that the replication of positive-strand RNA viruses of different supergroups is influenced by distinct groups of genes and that TBSV replication is associated with sets of genes that also have been associated with certain human disease states. Materials and MethodsYeast Strains and Expression Plasmids. Yeast strain 4741 and the YKO deletion series (10) were obtained from Open Biosystems (Huntsville, AL). Yeast transformation was modified from the standard lithium acetate (LiOAc)͞polyethylene glycol (PEG) protocol (16) to facilitate a 96-well plate format. Briefly, yeast strains were grown overnight in yeast extract͞peptone͞dextrose medium supplemented with 200 mg͞liter geneticin G418. Cultures were then diluted to Ϸ0.3 OD 600 in fresh medium (0.25 ml per well) and cultured for an additional 4 h at 30°C. The cells were pelleted, washed with sterile water, and resuspended in 0.1 M LiOAc. This procedure was followed by rep...

show abstract

“…The type of membranes involved in replication depends on the virus considered: tymoviruses, for instance, induce vesicular structures by invagination of chloroplast membranes in which both viral RNA and nonstructural proteins were detected (24,25), whereas infection by tombusviruses leads to the formation of multivesicular bodies derived from mitochondria or peroxisomes (9,56,57). Several plant viruses belonging to different groups, such as tobamoviruses (30), bromoviruses (50), potyviruses (59), and comoviruses (11), similarly appear to strongly modify the endomembrane compartments.…”

mentioning

confidence: 99%

“…In some cases, the transmembrane domains responsible for their anchoring on specific membranes could be identified (18,35,56) allowing the formation of dedicated structures where coupled translation and synthesis of both minus-and plus-strand RNA take place (8). Such complexes probably ensure protection of the viral RNA being synthesized from degradation by cellular RNases.…”

mentioning

confidence: 99%

Grapevine Fanleaf Virus Replication Occurs on Endoplasmic Reticulum-Derived Membranes

Ritzenthaler

Laporte

Gaire

et al. 2002

J Virol

View full text Add to dashboard Cite

Infection by Grapevine fanleaf nepovirus (GFLV), a bipartite RNA virus of positive polarity belonging to the Comoviridae family, causes extensive cytopathic modifications of the host endomembrane system that eventually culminate in the formation of a perinuclear "viral compartment." We identified by immunoconfocal microscopy this compartment as the site of virus replication since it contained the RNA1-encoded proteins necessary for replication, newly synthesized viral RNA, and double-stranded replicative forms. In addition, by using transgenic T-BY2 protoplasts expressing green fluorescent protein in the endoplasmic reticulum (ER) or in the Golgi apparatus (GA), we could directly show that GFLV replication induced a depletion of the cortical ER, together with a condensation and redistribution of ER-derived membranes, to generate the viral compartment. Brefeldin A, a drug known to inhibit vesicle trafficking between the GA and the ER, was found to inhibit GFLV replication. Cerulenin, a drug inhibiting de novo synthesis of phospholipids, also inhibited GFLV replication. These observations imply that GFLV replication depends both on ER-derived membrane recruitment and on de novo lipid synthesis. 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.

show abstract

Membrane Targeting Sequences in Tombusvirus Infections

Cited by 80 publications

References 28 publications

Mutation of a chloroplast-targeting signal in Alternanthera mosaic virus TGB3 impairs cell-to-cell movement and eliminates long-distance virus movement

Mutation of a chloroplast-targeting signal in Alternanthera mosaic virus TGB3 impairs cell-to-cell movement and eliminates long-distance virus movement

Yeast genome-wide screen reveals dissimilar sets of host genes affecting replication of RNA viruses

Grapevine Fanleaf Virus Replication Occurs on Endoplasmic Reticulum-Derived Membranes

Contact Info

Product

Resources

About