Publications

selective repression of translation by the brome mosaic virus 1a rna replication protein.	differential expression of viral replication proteins is essential for successful infection. we report here that overexpression of the brome mosaic virus (bmv) 1a protein can repress viral rna replication in a dosage-dependent manner. using rna replication-incompetent reporter constructs, repression of translation from bmv rna1 and rna2 was observed, suggesting that the effect on translation of the bmv rna replication proteins is responsible for the decrease in rna levels. furthermore, repressio ...	2007	17108036
core-controlled polymorphism in virus-like particles.	this study concerns the self-assembly of virus-like particles (vlps) composed of an icosahedral virus protein coat encapsulating a functionalized spherical nanoparticle core. the recent development of efficient methods for vlp self-assembly has opened the way to structural studies. using electron microscopy with image reconstruction, the structures of several vlps obtained from brome mosaic virus capsid proteins and gold nanoparticles were elucidated. varying the gold core diameter provides cont ...	2007	17227841
the effects of b, k10, and ar chromosomes on the resistance of maize to viral infection.	studies were conducted to determine if accessory (b) chromosomes, the abnormal tenth (k10) chromosome or the aberrant ratio (ar) phenomenon of maize (zea mays l.) affect the resistance of the plants to viral infection. genetically similar stocks of maize with and without these elements were compared to determine what effect they would have on the plants response to brome mosaic virus (bmv), maize dwarf mosaic virus (mdmv), wheat streak mosaic virus (wsmv) and barley stripe mosaic virus (bsmv).-t ...	1978	17248865
xenopus xp54 and human rck/p54 helicases functionally replace yeast dhh1p in brome mosaic virus rna replication.	by using a brome mosaic virus (bmv)-saccharomyces cerevisiae system, we previously showed that the cellular lsm1p-7p/pat1p/dhh1p decapping-activator complex functions in bmv rna translation and replication. as a first approach in investigating whether the corresponding human homologues play a similar role, we expressed human lsm1p (hlsm1p) and rck/p54 in yeast. expression of rck/p54 but not hlsm1p restored the defect in bmv rna translation and replication observed in the dhh1delta and lsm1delta ...	2007	17301158
rna-binding proteins that inhibit rna virus infection.	arrays of >5,000 saccharomyces cerevisiae proteins were screened to identify proteins that can preferentially bind a small rna hairpin that contains a clamped adenine motif (cam). a cam is required for the replication of brome mosaic virus (bmv), a plant-infecting rna virus that can replicate in s. cerevisiae. several hits were selected for further characterization in nicotiana benthamiana. pseudouridine synthase 4 (pus4) and the actin patch protein 1 (app1) modestly reduced bmv genomic plus-str ...	2007	17360619
replication-independent long-distance trafficking by viral rnas in nicotiana benthamiana.	viruses with separately encapsidated genomes could have their genomes introduced into different leaves of a plant, thus necessitating long-distance trafficking of the viral rnas for successful infection. to examine this possibility, individual or combinations of genome segments from the tripartite brome mosaic virus (bmv) were transiently expressed in leaves of nicotiana benthamiana plants using engineered agrobacterium tumefaciens. bmv rna3 was found to traffic from the initial site of expressi ...	2007	17416731
in vivo particle polymorphism results from deletion of a n-terminal peptide molecular switch in brome mosaic virus capsid protein.	the interaction between brome mosaic virus (bmv) coat protein (cp) and viral rna is a carefully orchestrated process resulting in the formation of homogeneous population of infectious virions with t=3 symmetry. expression in vivo of either wild type or mutant bmv cp through homologous replication never results in the assembly of aberrant particles. in this study, we report that deletion of amino acid residues 41-47 from the n-proximal region of bmv cp resulted in the assembly of polymorphic viri ...	2007	17449079
downregulation of the nbnaca1 gene encoding a movement-protein-interacting protein reduces cell-to-cell movement of brome mosaic virus in nicotiana benthamiana.	the 3a movement protein (mp) plays a central role in the movement of the rna plant virus, brome mosaic virus (bmv). to identify host factor genes involved in viral movement, a cdna library of nicotiana benthamiana, a systemic host for bmv, was screened with far-western blotting using a recombinant bmv mp as probe. one positive clone encoded a protein with sequence similarity to the alpha chain of nascent-polypeptide-associated complex from various organisms, which is proposed to contribute to th ...	2007	17555275
interactions between brome mosaic virus rnas and cytoplasmic processing bodies.	cytoplasmic processing bodies are sites where nontranslating mrnas accumulate for different fates, including decapping and degradation, storage, or returning to translation. previous work has also shown that the lsm1-7p complex, dhh1p, and pat1p, which are all components of p bodies, are required for translation and subsequent recruitment to replication of the plant virus brome mosaic virus (bmv) genomic rnas when replication is reproduced in yeast cells. to better understand the role of p bodie ...	2007	17609284
phosphorylation and interaction of the movement and coat proteins of brome mosaic virus in infected barley protoplasts.	the 3a movement protein (b3a) of brome mosaic virus (bmv) plays essential roles in the cell-to-cell movement of bmv. b3a is known to bind nucleic acids, to transport rna to neighbouring cells, and to form tubular structures. here, we tested the assumption that phosphorylation may be a mechanism that regulates b3a functions and showed that not only b3a but also the coat protein, bcp, was phosphorylated in bmv-infected barley protoplasts. both bcp and b3a were detected in a complex immunoprecipita ...	2007	17680322
bacterial gene inserted in an engineered rna virus: efficient expression in monocotyledonous plant cells.	brome mosaic virus (bmv) is a plant virus whose genome consists of three rna components. a previously described viral complementary dna expression system has been used to express both wild-type and altered genomic rna's in barley protoplasts. variants of bmv rna3 were constructed in which the coat gene had been removed or replaced with sequences encoding chloramphenicol acetyltransferase (cat). cat sequences were also inserted near the 5' end of the intact coat gene. when inoculated on protoplas ...	1986	17839568
replication-coupled packaging mechanism in positive-strand rna viruses: synchronized coexpression of functional multigenome rna components of an animal and a plant virus in nicotiana benthamiana cells by agroinfiltration.	flock house virus (fhv), a bipartite rna virus of insects and a member of the nodaviridae family, shares viral replication features with the tripartite brome mosaic virus (bmv), an rna virus that infects plants and is a member of the bromoviridae family. in bmv and fhv, genome packaging is coupled to replication, a widely conserved mechanism among positive-strand rna viruses of diverse origin. to unravel the events that modulate the mechanism of replication-coupled packaging, in this study, we h ...	2008	18032497
functional analysis of brome mosaic virus coat protein rna-interacting domains.	the coat proteins (cp) of cowpea chlorotic mottle (ccmv) and brome mosaic virus (bmv), two members of the genus bromovirus, share 70% identity at the amino acid (aa) level and contain four highly conserved regions, identified as putative rna-interacting domains (rids). to assess the contribution of the conserved aa sequence within each rid and the structural features contained therein toward virion assembly and rna packaging, we engineered a set of fourteen independent mutations (deletions and s ...	2008	18066637
cis- and trans-acting functions of brome mosaic virus protein 1a in genomic rna1 replication.	rna viruses employ a combination of mechanisms to regulate their gene expression and replication. brome mosaic virus (bmv) is a tripartite positive-strand rna virus used to study the requirements for virus infection. bmv genomic rna1 encodes protein 1a, which contains a methyltransferase (mt) domain and a helicase domain that are required for replication. 1a forms a complex with the 2a rna-dependent rna polymerase for the replication and transcription of all bmv rnas. rna1 expressed with 2a from ...	2008	18160434
biochemical analyses of the interactions between viral polymerases and rnas.	the interaction between viral polymerases and their cognate rnas is vital to regulate the timing and abundance of viral replication products. despite this, only minimal detailed information is available for the interaction between viral polymerases and cognate rnas. we study the biochemical interactions using two viral polymerases that could serve as models for other plus-strand rna viruses: the replicase from the tripartite brome mosaic virus (bmv), and the recombinant rna-dependent rna polymer ...	2008	18370256
rna encapsidation assay.	analysis of viral rna encapsidation assay provides a rapid means of assaying which of the progeny rna are competent for packaging into stable mature virions. generally, a parallel analysis of total rna and rna obtained from purified virions is advisable for accurate interpretation of the results. in this, we describe a series of in vivo assays in which viral rna encapsidation can be verified. these include whole plants inoculated either mechanically or by agroinfiltration and protoplasts. the en ...	2008	18370261
specificity of in vitro reconstitution of bromegrass mosaic virus.	bromegrass mosaic virus (bmv) rna was allowed to compete with yeast trna or alfalfa mosaic virus (amv) rna for in vitro encapsidation by bmv protein. various proportions of 32p-labeled foreign rnas were added to a reassembly mixture (bmv protein: bmv rna, 4:1) and the reassembly products were observed by analytical and rate-zonal sedimentation, and the rna contents of the nucleocapsids were examined by gel electrophoresis. incubation of bmv protein with trna alone produced 56 s particles contain ...	1979	18627894
rna polymerase activity and protein synthesis in brome mosaic virus-infected protoplasts.	rna-dependent rna polymerase activity and protein synthesis in brome mosaic virus (bmv)-infected and uninfected protoplasts were investigated during the course of viral replication. in protoplast homogenates, the membrane-bound rna polymerase activity resistant to actinomycin d was enhanced by bmv infection up to 30-fold that found in mock-inoculated protoplasts. the activity was first detected 7 to 8 hr postinfection. it reached a maximum at around 30 hr postinfection, then decreased gradually ...	1979	18631624
changes in the organization of bromegrass mosaic virus in response to cation binding as probed by changes in susceptibility to degradative enzymes.	the swelling at alkaline ph and the sensitivity of bromegrass mosaic virus to degradative enzymes are less in the presence of moderate concentrations of kc1 than at low salt concentration. the virus can be efficiently stabilized above neutral ph by divalent metal cations, especially ca2+, but this effect is antagonized by kc1. polyamines also can stabilize the virus, but the salt concentrations for optimal protection of the viral rna and protein moieties are then different, as judged by their su ...	1980	18631645
sequence of the 3' untranslated region of brome mosaic virus coat protein messenger rna.	the 3' terminal 337 bases of bmv (brome mosaic virus) coat protein mrna (bmv rna4) are presented. this sequence includes the terminal portion of the coat protein cistron and the complete 300-base 3' noncoding sequence. the 3' noncoding sequence displays significant complementarity to the 5' terminal sequence of bmv rna3 but not to the 5' terminal sequence of bmv rna4.	1980	18631666
double infection of tobacco protoplasts with brome mosaic virus and cowpea chlorotic mottle virus.	mixed infections of tobacco protoplasts with cowpea chlorotic mottle virus (ccmv) and brome mosaic virus (bmv) have been studied. fluorescent antibody staining showed that capsids of both viruses were made in doubly infected protoplasts but only infectious bmv could be recovered, i.e., bmv dominated in mixed infections and prevented synthesis of infectious ccmv. healthy protoplasts could be infected after several hours in culture but the susceptibility to infection decreased with time in culture ...	1980	18631680
a t = 1 capsid formed by protein of brome mosaic virus in the presence of trypsin.	in the presence of trypsin, the coat protein of brome mosaic virus (bmv) has been observed to polymerize in a d2o buffer at pd 7.6 to form a small empty capsid with triangulation number t = 1. normally, this same protein polymerizes at acidic ph to form empty capsids with t = 3. the trypsin is shown to remove 63 amino acids on the n terminus side leaving a polypeptide chain of mr 13,500. the kinetics of formation of this small particle have been followed by neutron scattering. further, the parti ...	1981	18635045
viral protein synthesis in barley protoplasts inoculated with native and fractionated brome mosaic virus rna.	when barley protoplasts were inoculated with brome mosaic virus (bmv) rnas 1 and 2, there was a pronounced synthesis of the 110,000- and 100,000-dalton virally coded proteins. in contrast, there was no detectable synthesis of any viral proteins following inoculation with rna 3 alone or rna 4 alone. when rnas 1 and 2 were recombined with rna 3 in the inoculum, the profile of proteins synthesized was identical to that following inoculation with similar quantities of unfractionated bmv rna; i.e., t ...	1981	18635079
the specific involvement of coat protein in tobacco mosaic virus cross protection.	nicotiana sylvestris infected by strains of tobacco mosaic virus (tmv) causing mosaic can be superinfected in the dark green leaf tissue, but not light green tissue, by necrotizing strains of tmv. the dark green tissue, however, is much less susceptible than healthy tissue, to some extent, even to unrelated viruses. the rna of necrotizing strains of tmv was relatively more infectious than intact virus on mosaic than on healthy leaves and caused lesions in both light and dark green tissues. the s ...	1982	18635142
use of dodecyl-beta-d-maltoside in the purification and stabilization of rna polymerase from brome mosaic virus-infected barley.	the activity and specificity of rna-dependent rna polymerase (replicase) isolated from brome mosaic virus-infected barley was enhanced by extraction with the nonionic detergent dodecyl-beta-d-maltoside. the enzyme was stable for at least 8 weeks when stored at -70 degrees . a further 100-fold purification was obtained by centrifugation through sucrose in the presence of detergent. the polymerase activity was associated with the pellet fraction; the template dependence and specificity were simila ...	1982	18635149
role of trna-like structures in controlling plant virus replication.	transfer rna-like structures (tlss) that are sophisticated functional mimics of trnas are found at the 3'-termini of the genomes of a number of plant positive strand rna viruses. three natural aminoacylation identities are represented: valine, histidine, and tyrosine. paralleling this variety in structure, the roles of tlss vary widely between different viruses. for turnip yellow mosaic virus, the tls must be capable of valylation in order to support infectivity, major roles being the provision ...	2009	18638511
plant virus-specific transport function. ii. a factor controlling virus host range.	an experimental system allowing the transport of the dependent virus from the conducting tissues into the leaf mesophyll of a plant preinfected by the helper virus has been developed recently [taliansky et al. (1982). virology 122, 318-326]. the role of virus-specific transport function in the host range control of a plant virus was studied here by this technique. it was shown that tm-2 tomato lines (in which the resistance to tmv is expressed only at the level of the intact plant, but not in pr ...	1982	18638809
use of micrococcal nuclease in the purification of highly template dependent rna-dependent rna polymerase from brome mosaic virus-infected barley.	the template dependence of rna-dependent rna polymerase from brome mosaic virus (bmv)-infected barley was greatly increased by micrococcal nuclease digestion of the endogenous rna. [32p]ump incorporation by the nuclease-treated enzyme was stimulated 20-fold when bmv rna was added as template, while incorporation by the untreated enzyme was stimulated only 5-fold by the addition of bmv rna. other properties of bmv polymerase were not changed significantly by nuclease digestion. the extract remain ...	1983	18638891
primary structure of brome mosaic virus coat protein.	the amino acid sequence of bmv (brome mosaic virus) coat protein is presented and compared with the sequence derived from rna structure. apart from removal of the n-terminal methionine residue and acetylation of the following serine residue, no post-translational modifications occur.	1983	18639120
rna-dependent rna polymerase isolated from cowpea chlorotic mottle virus-infected cowpeas is specific for bromoviral rna.	an rna-dependent rna polymerase activity capable of synthesizing full length double-stranded rna products only in the presence of bromoviral rna templates has been isolated from cowpea chlorotic mottle virus (ccmv)-infected cowpeas. no comparable discrete products were obtained when a nonbromoviral (cowpea mosaic virus) rna was used as template. heterodisperse, ribonuclease-sensitive products were obtained in reactions catalyzed by similar extracts from mock-inoculated (uninfected) plants in the ...	1984	18639798
specificity of rna and coat protein interaction in alfalfa mosaic virus and related viruses.	well-defined coat protein binding sites were found to be present on the genomic rnas of almv and tsv. in view of the regulatory importance of these sites in virus multiplication, the possibility that nonrelated proteins also were able to interact with these sites was investigated. the coat proteins of tsv, bmv, cmv, and sbmv recognize specific sites on almv rna 1. the significance of these sites in virus multiplication is discussed. no specific binding sites were found with tmv coat protein or t ...	1985	18639837
swelling of isometric and of bacilliform plant virus nucleocapsids is required for virus-specific protein synthesis in vitro.	encapsidated rna of cowpea chlorotic mottle virus (ccmv), brome mosaic virus (bmv), alfalfa mosaic virus, and southern bean mosaic virus can act as templates for protein synthesis when preswollen virions are added to a wheat germ extract, or when unswollen virions swell in the extract. encapsidated rna of turnip yellow mosaic virus, whose particles are unlikely to swell under the conditions used here, did not act as a template. ccmv and bmv, swollen in the extract, gave relatively more rna 1 and ...	1986	18640565
inoculation of protoplasts with viruses by electroporation.	optimal conditions for electroporation have been determined using inoculation of brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) and its rna into protoplasts of nicotiana tabacum and n. plumbaginifolia. the most satisfactory medium was 0.5-0.7 m mannitol; calcium ions were toxic and other electrolytes were not helpful during electroporation. brief pulses (ca. 10 microsec) were less destructive to the protoplasts than longer ones (ca. 10 msec) and gave high percentage infections ...	1987	18644555
brome mosaic virus coat protein inhibits viral rna synthesis in vitro.	in vitro, the coat protein of brome mosaic virus (bmv) inhibited rna synthesis by replicase extracted from bmv-infected barley leaves. the inhibition was due to the interaction of coat protein with bmv rna. under the same conditions, no inhibition by tmv coat protein or bovine serum albumin was detected. for the complete inhibition of rna synthesis in vitro, a coat protein:rna ratio of 620:1 was required, and their preincubation before addition to the reaction mixture was essential. if the coat ...	1987	18644560
high efficiency t7 polymerase synthesis of infectious rna from cloned brome mosaic virus cdna and effects of 5' extensions on transcript infectivity.	addition of a single extra 5' g residue reduces the infectivity of transcripts from cloned bmv cdna no more than threefold, while addition of 7- or 16-base 5' extensions to rna3 transcripts dramatically suppresses their biological activity. moreover, despite resultant alteration of the promoter consensus sequence, fusion of bmv cdna directly to the initiation site of the canonical phi10 promoter of bacteriophage t7 allows efficient in vitro synthesis of infectious bmv transcripts by t7 rna polym ...	1987	18644564
self-assembly of brome mosaic virus capsids: insights from shorter time-scale experiments.	an amended kinetic model for the self-assembly of empty capsids of brome mosaic virus is proposed. the model has been modified to account for a new feature in the assembly kinetics revealed by time-course light scattering experiments at higher temporal resolution than previously attempted. to be able to simulate the sharp takeoff from the initial lag phase to the growth phase in the kinetic curves, a monomer activation step was proposed.	2008	18754598
depurination of brome mosaic virus rna3 in vivo results in translation-dependent accelerated degradation of the viral rna.	pokeweed antiviral protein (pap) is a ribosome-inactivating protein isolated from the pokeweed plant (phytolacca americana) that exhibits antiviral activity against several plant and animal viruses. we have shown previously that pap depurinates brome mosaic virus (bmv) rnas in vitro and that prior incubation of these rnas with pap reduced their synthesis in barley protoplasts. to investigate the post-transcriptional effect of pap on viral rna in vivo, we transcribed bmv rna3 and expressed pap in ...	2008	18815133
virus infection improves drought tolerance.	viruses are obligate intracellular symbionts. plant viruses are often discovered and studied as pathogenic parasites that cause diseases in agricultural plants. however, here it is shown that viruses can extend survival of their hosts under conditions of abiotic stress that could benefit hosts if they subsequently recover and reproduce. various plant species were inoculated with four different rna viruses, brome mosaic virus (bmv), cucumber mosaic virus (cmv), tobacco mosaic virus and tobacco ra ...	2008	18823313
translation inhibition of capped and uncapped viral rnas mediated by ribosome-inactivating proteins.	abstract ribosome-inactivating proteins (rips) are n-glycosidases that remove specific purine residues from the sarcin/ricin (s/r) loop of the large rrna and arrest protein synthesis at the translocation step. in addition to their enzymatic activity, rips have been reputed to be potent antiviral agents against many plant, animal, and human viruses. we recently showed that pokeweed antiviral protein (pap), an rip from pokeweed, inhibits translation in cell extracts by binding to the cap structure ...	2003	18942981
presence of brome mosaic virus in barley guttation fluid and its association with localized cell death response.	abstract water exits from inside the leaf through transpiration or guttation. under conditions to promote guttation, surface fluid (guttation fluid) from brome mosaic virus (bmv)-infected barley, wheat, and maize plants was analyzed for the presence of the virus by biological and serological assays. we also investigated the route by which bmv exited infected cells to the intercellular space of the barley leaf. bmv was detected in guttation fluid from systemically infected barley leaves when the ...	2001	18943588
small-scale isolation of viral rna-dependent rna polymerase from protoplasts inoculated with in vitro transcripts.	cowpea chlorotic mottle virus (ccmv) replicated in tobacco suspension cell protoplasts inoculated with in vitro transcripts of ccmv rna1, 2, and 3. ccmv rna-dependent rna polymerase (rdrp) isolated from these protoplasts specifically recognized ccmv and brome mosaic virus (bmv) subgenomic rna promoters and directed in vitro rna synthesis in a manner indistinguishable from ccmv rdrp more laboriously isolated from systemically infected cowpea leaves. omission of ccmv rna3 from the protoplast inocu ...	2001	18944031
defective movement of viruses in the family bromoviridae is differentially complemented in nicotiana benthamiana expressing tobamovirus or dianthovirus movement proteins.	abstract taxonomically distinct tobacco mosaic tobamovirus (tmv), red clover necrotic mosaic dianthovirus (rcnmv), cucumber mosaic cucumovirus (cmv), brome mosaic bromovirus (bmv), and cowpea chlorotic mottle bromovirus (ccmv) exhibit differences in their host range. each of these viruses encodes a functionally similar nonstructural movement protein (mp) that is essential for cell-to-cell movement of a progeny virus. despite the lack of significant amino acid identity among the mps of cmv, tmv, ...	1998	18944938
mechanisms of size control and polymorphism in viral capsid assembly.	we simulate the assembly dynamics of icosahedral capsids from subunits that interconvert between different conformations (or quasi-equivalent states). the simulations identify mechanisms by which subunits form empty capsids with only one morphology but adaptively assemble into different icosahedral morphologies around nanoparticle cargoes with varying sizes, as seen in recent experiments with brome mosaic virus (bmv) capsid proteins. adaptive cargo encapsidation requires moderate cargo-subunit i ...	2008	18950240
tobacco mosaic virus 126-kda protein increases the susceptibility of nicotiana tabacum to other viruses and its dosage affects virus-induced gene silencing.	the tobacco mosaic virus (tmv) 126-kda protein is a suppressor of rna silencing previously shown to delay the silencing of transgenes in nicotiana tabacum and n. benthamiana. here, we demonstrate that expression of a 126-kda protein-green fluorescent protein (gfp) fusion (126-gfp) in n. tabacum increases susceptibility to a broad assortment of viruses, including alfalfa mosaic virus, brome mosaic virus, tobacco rattle virus (trv), and potato virus x. given its ability to enhance trv infection in ...	2008	18986250
depurination within the intergenic region of brome mosaic virus rna3 inhibits viral replication in vitro and in vivo.	pokeweed antiviral protein (pap) is a glycosidase of plant origin that has been shown to depurinate some viral rnas in vitro. we have demonstrated previously that treatment of brome mosaic virus (bmv) rnas with pap inhibited their translation in a cell-free system and decreased their accumulation in barley protoplasts. in the current study, we map the depurination sites on bmv rna3 and describe the mechanism by which replication of the viral rna is inhibited by depurination. specifically, we dem ...	2008	19004869
genetic analysis of a host determination mechanism of bromoviruses in arabidopsis thaliana.	brome mosaic virus (bmv) and spring beauty latent virus (sblv) are closely related, tripartite rna plant viruses. in arabidopsis thaliana, bmv shows limited multiplication whereas sblv efficiently multiplies. such distinct multiplication abilities have been observed commonly in all arabidopsis accessions tested. we used this model system to analyze the molecular mechanism of viral resistance in plants at the species level. unlike sblv, bmv multiplication was limited even in protoplasts and a rea ...	2009	19059442
production of cucumber mosaic virus rna5 and its role in recombination.	cucumber mosaic virus (cmv) is a plant infecting tripartite positive-strand rna virus. in addition to three genomic and two known subgenomic rnas, cmv strains of subgroup ii (e.g. q-cmv), but not subgroup i (e.g. fny-cmv), produce and package a redundant rna5 encompassing the 3' 304-307 nucleotides of rnas 2 and 3. the mechanism regulating rna5 production and its role in cmv life cycle is unknown. in this study, transient expression of q2 or q3 by agroinfiltration into nicotiana benthamiana plan ...	2009	19059620
translation elongation factor 1a is a component of the tombusvirus replicase complex and affects the stability of the p33 replication co-factor.	host rna-binding proteins are likely to play multiple, integral roles during replication of plus-strand rna viruses. to identify host proteins that bind to viral rnas, we took a global approach based on the yeast proteome microarray, which contains 4080 purified yeast proteins. the biotin-labeled rna probes included two distantly related rna viruses, namely tomato bushy stunt virus (tbsv) and brome mosaic virus (bmv). altogether, we have identified 57 yeast proteins that bound to tbsv rna and/or ...	2009	19131084
comparison and functional implications of the 3d architectures of viral trna-like structures.	rna viruses co-opt the host cell's biological machinery, and their infection strategies often depend on specific structures in the viral genomic rna. examples are trna-like structures (tlss), found at the 3' end of certain plant viral rnas, which can use the cell's aminoacyl trna-synthetases (aarss) to drive addition of an amino acid to the 3' end of the viral rna. tlss are multifunctional rnas involved in processes such as viral replication, translation, and viral rna stability; these functions ...	2009	19144910
brome mosaic virus capsid protein regulates accumulation of viral replication proteins by binding to the replicase assembly rna element.	viruses provide valuable insights into the regulation of molecular processes. brome mosaic virus (bmv) is one of the simplest entities with four viral proteins and three genomic rnas. here we report that the bmv capsid protein (cp), which functions in rna encapsidation and virus trafficking, also represses viral rna replication in a concentration-dependent manner by inhibiting the accumulation of the rna replication proteins. expression of the replication protein 2a in trans can partially rescue ...	2009	19237464
longidorus breviannulatus as a vector for brome mosaic virus.		1987	19290121
a theory for viral capsid assembly around electrostatic cores.	we develop equilibrium and kinetic theories that describe the assembly of viral capsid proteins on a charged central core, as seen in recent experiments in which brome mosaic virus capsids assemble around nanoparticles functionalized with polyelectrolyte. we model interactions between capsid proteins and nanoparticle surfaces as the interaction of polyelectrolyte brushes with opposite charge using the nonlinear poisson boltzmann equation. the models predict that there is a threshold density of f ...	2009	19317561
an amphipathic alpha-helix controls multiple roles of brome mosaic virus protein 1a in rna replication complex assembly and function.	brome mosaic virus (bmv) protein 1a has multiple key roles in viral rna replication. 1a localizes to perinuclear endoplasmic reticulum (er) membranes as a peripheral membrane protein, induces er membrane invaginations in which rna replication complexes form, and recruits and stabilizes bmv 2a polymerase (2a(pol)) and rna replication templates at these sites to establish active replication complexes. during replication, 1a provides rna capping, ntpase and possibly rna helicase functions. here we ...	2009	19325881
rna binding by the brome mosaic virus capsid protein and the regulation of viral rna accumulation.	viral capsid proteins (cps) can regulate gene expression and encapsulate viral rnas. low-level expression of the brome mosaic virus (bmv) cp was found to stimulate viral rna accumulation, while higher levels inhibited translation and bmv rna replication. regulation of translation acts through an rna element named the b box, which is also critical for the replicase assembly. the bmv cp has also been shown to preferentially bind to an rna element named slc that contains the core promoter for genom ...	2009	19481091
vibrational dynamics of icosahedrally symmetric biomolecular assemblies compared with predictions based on continuum elasticity.	coarse-grained elastic network models elucidate the fluctuation dynamics of proteins around their native conformations. low-frequency collective motions derived by simplified normal mode analysis are usually involved in biological function, and these motions often possess noteworthy symmetries related to the overall shape of the molecule. here, insights into these motions and their frequencies are sought by considering continuum models with appropriate symmetry and boundary conditions to approxi ...	2009	19486668
translation and replication of hepatitis c virus genomic rna depends on ancient cellular proteins that control mrna fates.	inevitably, viruses depend on host factors for their multiplication. here, we show that hepatitis c virus (hcv) rna translation and replication depends on rck/p54, lsm1, and patl1, which regulate the fate of cellular mrnas from translation to degradation in the 5'-3'-deadenylation-dependent mrna decay pathway. the requirement of these proteins for efficient hcv rna translation was linked to the 5' and 3' untranslated regions (utrs) of the viral genome. furthermore, lsm1-7 complexes specifically ...	2009	19628699
the brome mosaic virus-based recombination vector triggers a limited gene silencing response depending on the orientation of the inserted sequence.	in some rna viruses (e.g. in brome mosaic virus, bmv), the same factor (intra- or intermolecular hybridization between viral rna molecules) is capable of inducing two different processes: rna silencing and rna recombination. to determine whether there is some interplay between these two phenomena, we have examined if the bmv-based recombination vector containing a plant-genome-derived sequence can function as a gene-silencing vector. surprisingly, we found that neither dsrna forming during the r ...	2010	19937458
improving small-angle x-ray scattering data for structural analyses of the rna world.	defining the shape, conformation, or assembly state of an rna in solution often requires multiple investigative tools ranging from nucleotide analog interference mapping to x-ray crystallography. a key addition to this toolbox is small-angle x-ray scattering (saxs). saxs provides direct structural information regarding the size, shape, and flexibility of the particle in solution and has proven powerful for analyses of rna structures with minimal requirements for sample concentration and volumes. ...	2010	20106957
lsm1-7 complexes bind to specific sites in viral rna genomes and regulate their translation and replication.	lsm1-7 complexes promote cellular mrna degradation, in addition to translation and replication of positive-strand rna viruses such as the brome mosaic virus (bmv). yet, how lsm1-7 complexes act on their targets remains elusive. here, we report that reconstituted recombinant lsm1-7 complexes directly bind to two distinct rna-target sequences in the bmv genome, a trna-like structure at the 3'-untranslated region and two internal a-rich single-stranded regions. importantly, in vivo analysis shows t ...	2010	20181739
lessons learned from the core rna promoters of brome mosaic virus and cucumber mosaic virus.	summary rna core promoters are nucleotide sequences needed to direct proper initiation of viral rna synthesis by the viral replicase. minimal length core promoter-templates that can direct accurate initiation of the genomic plus-, genomic minus-, and subgenomic rnas of brome mosaic virus and cucumber mosaic virus were characterized in previous works. several common themes and differences were observed in how each of the core promoters directed the initiation of viral rna synthesis in vitro. thes ...	2002	20569308
brome mosaic virus, good for an rna virologist's basic needs.	abstract taxonomic relationship: type member of the bromovirus genus, family bromoviridae. a member of the alphavirus-like supergroup of positive-sense single-stranded rna viruses. physical properties: virions are nonenveloped icosahedrals made up of 180 coat protein subunits (fig. 1). the particles are 26 nm in diameter and contain 22% nucleic acid and 78% protein. the bmv genome is composed of three positive-sense, capped rnas: rna1 (3.2 kb), rna2 (2.9 kb), rna3 (2.1 kb) (fig. 2). viral protei ...	2000	20572956
genomic plus-strand rna synthesis by the brome mosaic virus (bmv) rna replicase requires a sequence that is complementary to the binding site of the bmv helicase-like protein.	summary initiation of genomic plus-strand rna synthesis by the brome mosaic virus (bmv) replicase in vitro requires a 26-nucleotide (nt) rna sequence at the 3' end of the minus-strand rna and a nontemplated nucleotide 3' of the initiation cytidylate [sivakumaran, k. and kao, c.c. (1999)j. virol.64, 6415-6423]. at the 5' end of this rna is a 9-nt sequence called the cb box, the complement of the previously defined b box. the cb box can not be functionally replaced by the b box and has specific po ...	2000	20572981
role of surface charge density in nanoparticle-templated assembly of bromovirus protein cages.	self-assembling icosahedral protein cages have potentially useful physical and chemical characteristics for a variety of nanotechnology applications, ranging from therapeutic or diagnostic vectors to building blocks for hierarchical materials. for application-specific functional control of protein cage assemblies, a deeper understanding of the interaction between the protein cage and its payload is necessary. protein-cage encapsulated nanoparticles, with their well-defined surface chemistry, all ...	2010	20575505
membrane-shaping host reticulon proteins play crucial roles in viral rna replication compartment formation and function.	positive-strand rna viruses replicate their genomes on membranes with virus-induced rearrangements such as single- or double-membrane vesicles, but the mechanisms of such rearrangements, including the role of host proteins, are poorly understood. brome mosaic virus (bmv) rna synthesis occurs in ≈70 nm, negatively curved endoplasmic reticulum (er) membrane invaginations induced by multifunctional bmv protein 1a. we show that bmv rna replication is inhibited 80-90% by deleting the reticulon homolo ...	2010	20805477
a simple and general method for determining the protein and nucleic acid content of viruses by uv absorbance.	uv spectra of viruses are complicated by overlapping protein and rna absorbance and light scattering. we describe and validate methodology for estimating rna and protein concentration from such spectra. importantly, we found that encapsidation did not substantially affect rna absorbance. combining absorbance data with a known t number, we confirmed that brome mosaic virus packages about 3100 nucleotides/capsid, consistent with its genome. e. coli-expressed hepatitis b virus (hbv) packages host r ...	2010	20850162
effects of amino-acid substitutions in the brome mosaic virus capsid protein on rna encapsidation.	brome mosaic virus (bmv) packages its genomic rnas (rna1, rna2, and rna3) and subgenomic rna4 into three different particles. however, since the rnas in the virions have distinct lengths and electrostatic charges, we hypothesize that subsets of the virions should have distinct properties. a glutamine to cysteine substitution at position 120 of the capsid protein (cp) was found to result in a mutant virus named qc that exhibited a dramatically altered ratio of the rnas in virions. rna2 was far mo ...	2010	20923351
systemic virus-induced gene silencing allows functional characterization of maize genes during biotrophic interaction with ustilago maydis.	infection of maize (zea mays) plants with the corn smut fungus ustilago maydis leads to the formation of large tumors on the stem, leaves and inflorescences. in this biotrophic interaction, plant defense responses are actively suppressed by the pathogen, and previous transcriptome analyses of infected maize plants showed massive and stage-specific changes in host gene expression during disease progression. to identify maize genes that are functionally involved in the interaction with u. maydis, ...	2010	21039559
cell-penetrating peptides derived from viral capsid proteins.	cell-penetrating peptides (cpp) can translocate across the cell membrane and have been extensively studied for the delivery of proteins, nucleic acids, and therapeutics in mammalian cells. however, characterizations of cpp in plants have only recently been initiated. we showed that the intact virion and a recombinant capsid protein (cap) from a plant-infecting nonenveloped icosahedral rna virus, brome mosaic virus (bmv), can penetrate the membranes of plant protoplasts but are trapped by the ext ...	2011	21138375
subcellular localization and rearrangement of endoplasmic reticulum by brome mosaic virus capsid protein.	genome packaging in the plant-infecting brome mosaic virus (bmv), a member of the alphavirus-like superfamily, as well as in other positive-strand rna viruses pathogenic to humans (e.g., poliovirus) and animals (e.g., flock house virus), is functionally coupled to replication. although the subcellular localization site of bmv replication has been identified, that of the capsid protein (cp) has remained elusive. in this study, the application of immunofluorescence confocal microscopy to nicotiana ...	2011	21209103
optical nano-constructs composed of genome-depleted brome mosaic virus doped with a near infrared chromophore for potential biomedical applications.	we have engineered an optical nanoconstruct composed of genome-depleted brome mosaic virus doped with indocyanine green (icg), an fda-approved near-infrared (nir) chromophore. constructs are highly monodispersed with standard deviation of ±3.8 nm from a mean diameter of 24.3 nm. they are physically stable and exhibit a high degree of optical stability at physiological temperature (37 °c). using human bronchial epithelial cells, we demonstrate the effectiveness of the constructs for intracellular ...	2011	21210643
intersection of the multivesicular body pathway and lipid homeostasis in rna replication by a positive-strand rna virus.	like many positive-strand rna viruses, brome mosaic virus (bmv) rna replication occurs in membrane-invaginated vesicular compartments. bmv rna replication compartments show parallels with membrane-enveloped, budding retrovirus virions, whose release depends on the cellular multivesicular body (mvb) sorting pathway. bmv rna replication compartments are not released from their parent membranes, but might depend on mvb functions for membrane invagination. prior results show that bmv rna replication ...	2011	21430061
magnetic virus-like nanoparticles in n. benthamiana plants: a new paradigm for environmental and agronomic biotechnological research.	this article demonstrates the encapsulation of cubic iron oxide nanoparticles (nps) by brome mosaic virus capsid shells and the formation, for the first time, of virus-based nanoparticles (vnps) with cubic cores. cubic iron oxide nps functionalized with phospholipids containing poly(ethylene glycol) tails and terminal carboxyl groups exhibited exceptional relaxivity in magnetic resonance imaging experiments, which opens the way for in vivo mri studies of systemic virus movement in plants. prelim ...	2011	21452886
the coat protein leads the way: an update on basic and applied studies with the brome mosaic virus coat protein.	the brome mosaic virus (bmv) coat protein (cp) accompanies the three bmv genomic rnas and the subgenomic rna into and out of cells in an infection cycle. in addition to serving as a protective shell for all of the bmv rnas, cp plays regulatory roles during the infection process that are mediated through specific binding of rna elements in the bmv genome. one regulatory rna element is the b box present in the 5' untranslated region (utr) of bmv rna1 and rna2 that play important roles in the forma ...	2011	21453435
p bodies inhibit retrotransposition of endogenous intracisternal a particles.	mrna processing bodies (p bodies) are cytoplasmic foci that contain translationally-repressed mrna. since they are important for the retrotransposition of ty elements and brome mosaic virus in yeast cells, we assessed the role of p bodies in the movement of endogenous intracisternal a particles (iaps) in mammalian cells. in contrast to these other systems, their disruption via knockdown of rck or eif4e-t rather increased iap retrotransposition as well as levels of iap transcripts, gag proteins a ...	2011	21525359
rna-rna recombination in plant virus replication and evolution.	rna-rna recombination is one of the strongest forces shaping the genomes of plant rna viruses. the detection of recombination is a challenging task that prompted the development of both in vitro and in vivo experimental systems. in the divided genome brome mosaic virus system, both inter- and intrasegmental crossovers are described. other systems utilize satellite or defective interfering rnas of turnip crinkle virus, tomato bushy stunt virus, cucumber necrosis virus, and potato virus x. these a ...	2010	21529157
depurination of brome mosaic virus rna3 inhibits its packaging into virus particles.	packaging of the segmented rna genome of brome mosaic virus (bmv) into discrete particles is an essential step in the virus life cycle; however, questions remain regarding the mechanism of rna packaging and the degree to which the viral coat protein controls the process. in this study, we used a plant-derived glycosidase, pokeweed antiviral protein, to remove 14 specific bases from bmv rna3 to examine the effect of depurination on virus assembly. depurination of a771 within orf3 and a1006 in the ...	2011	21609957
packaging and structural phenotype of brome mosaic virus capsid protein with altered n-terminal β-hexamer structure.	the first 45 amino acid region of brome mosaic virus (bmv) capsid protein (cp) contains rna binding and structural domains that are implicated in the assembly of infectious virions. one such important structural domain encompassing amino acids 28qpviv32, highly conserved between bmv and cowpea chlorotic mottle virus (ccmv), exhibits a β-hexamer structure. in this study we report that alteration of the β-hexamer structure by mutating 28qpviv32 to 28aaaaa32 had no effect either on symptom phenotyp ...	2011	21864876
Systematic identification of novel, essential host genes affecting bromovirus RNA replication.	Positive-strand RNA virus replication involves viral proteins and cellular proteins at nearly every replication step. Brome mosaic virus (BMV) is a well-established model for dissecting virus-host interactions and is one of very few viruses whose RNA replication, gene expression and encapsidation have been reproduced in the yeast Saccharomyces cerevisiae. Previously, our laboratory identified ~100 non-essential host genes whose loss inhibited or enhanced BMV replication at least 3-fold. However, ...	2011	21915247
Mutations in the Antiviral RNAi Defense Pathway Modify Brome mosaic virus RNA Recombinant Profiles.	RNA interference (RNAi) mechanism targets viral RNA for degradation. To test whether RNAi gene products contributed to viral RNA recombination, a series of Arabidopsis thaliana RNAi-defective mutants were infected with Brome mosaic virus (BMV) RNAs that have been engineered to support crossovers within the RNA3 segment. Single-cross RNA3-RNA1, RNA3-RNA2, and RNA3-RNA3 recombinants accumulated in both the wild-type (wt) and all knock-out lines at comparable frequencies. However, a reduced accumul ...	2012	21936664
top 10 plant viruses in molecular plant pathology.	many scientists, if not all, feel that their particular plant virus should appear in any list of the most important plant viruses. however, to our knowledge, no such list exists. the aim of this review was to survey all plant virologists with an association with molecular plant pathology and ask them to nominate which plant viruses they would place in a 'top 10' based on scientific/economic importance. the survey generated more than 250 votes from the international community, and allowed the gen ...	2011	22017770
Bromovirus RNA Replication Compartment Formation Requires Concerted Action of 1a's Self-Interacting RNA Capping and Helicase Domains.	All positive-strand RNA viruses replicate their genomes in association with rearranged intracellular membranes such as single- or double-membrane vesicles. Brome mosaic virus (BMV) RNA synthesis occurs in vesicular endoplasmic reticulum (ER) membrane invaginations, each induced by many copies of viral replication protein 1a, which has N-terminal RNA capping and C-terminal helicase domains. Although the capping domain is responsible for 1a membrane association and ER targeting, neither this domai ...	2012	22090102
Quantitation of hepatitis delta virus using a single-step internally controlled real-time RT-qPCR and a full-length genomic RNA calibration standard.	Quantitation of circulating hepatitis delta virus (HDV) RNA is important for assessing the response to antiviral therapy and for understanding the complex dynamic interactions between hepatitis B virus (HBV) and HDV replication. Although several PCR assays for HDV RNA have been described none of them incorporate an internal control or use a full-length RNA calibration standard for absolute quantitation. This study describes the development and evaluation of a novel single-step real-time RT-qPCR ...	2012	22108292
two loci in sorghum with nb-lrr encoding genes confer resistance to colletotrichum sublineolum.	the aim of this work was to identify plant resistance genes to the sorghum anthracnose fungus colletotrichum sublineolum. cdna-aflp transcript profiling on two contrasting sorghum genotypes inoculated with c. sublineolum generated about 3,000 informative fragments. in a final set of 126 sequenced genes, 15 were identified as biotic stress related. seven of the plant-derived genes were selected for functional analysis using a brome mosaic virus-based virus-induced gene silencing (vigs) system fol ...	2011	22143275
rna synthesis by the brome mosaic virus rna-dependent rna polymerase in human cells reveals requirements for de novo initiation and protein-protein interaction.	brome mosaic virus (bmv) is a model positive-strand rna virus whose replication has been studied in a number of surrogate hosts. in transiently transfected human cells, the bmv polymerase 2a activated signaling by the innate immune receptor rig-i, which recognizes de novo-initiated non-self-rnas. active-site mutations in 2a abolished rig-i activation, and coexpression of the bmv 1a protein stimulated 2a activity. mutations previously shown to abolish 1a and 2a interaction prevented the 1a-depend ...	2012	22318148
host acyl coenzyme a binding protein regulates replication complex assembly and activity of a positive-strand rna virus.	all positive-strand rna viruses reorganize host intracellular membranes to assemble their replication complexes. similarly, brome mosaic virus (bmv) induces two alternate forms of membrane-bound rna replication complexes: vesicular spherules and stacks of appressed double-membrane layers. the mechanisms by which these membrane rearrangements are induced, however, remain unclear. we report here that host acb1-encoded acyl coenzyme a (acyl-coa) binding protein (acbp) is required for the assembly a ...	2012	22345450
emergence of distinct brome mosaic virus recombinants is determined by the polarity of the inoculum rna.	despite overwhelming interest in the impact exerted by recombination during evolution of rna viruses, the relative contribution of the polarity of inoculum templates remains poorly understood. here, by agroinfiltrating nicotiana benthamiana leaves, we show that brome mosaic virus (bmv) replicase is competent to initiate positive-strand [(+)-strand] synthesis on an ectopically expressed rna3 negative strand [(-) strand] and faithfully complete the replication cycle. consequently, we sought to exa ...	2012	22357282
the subgenomic promoter of brome mosaic virus folds into a stem-loop structure capped by a pseudo-triloop that is structurally similar to the triloop of the genomic promoter.	in brome mosaic virus, both the replication of the genomic (+)-rna strands and the transcription of the subgenomic rna are carried out by the viral replicase. the production of (-)-rna strands is dependent on the formation of an aua triloop in the stem-loop c (slc) hairpin in the 3'-untranslated region of the (+)-rna strands. two alternate hypotheses have been put forward for the mechanism of subgenomic rna transcription. one posits that transcription commences by recognition of at least four ke ...	2012	22393035
simple and robust in vivo and in vitro approach for studying virus assembly.	in viruses with positive-sense rna genomes pathogenic to humans, animals and plants, progeny encapsidation into mature and stable virions is a cardinal phase during establishment of infection in a given host. consequently, study of encapsidation deciphers the information regarding the know-how of the mechanism regulating virus assembly to form infectious virions. such information is vital in formulating novel methods of curbing virus spread and disease control. virus encapsidation can be studied ...	2012	22410612
a physical interaction between viral replicase and capsid protein is required for genome-packaging specificity in an rna virus.	genome packaging is functionally coupled to replication in rna viruses pathogenic to humans (poliovirus), insects (flock house virus [fhv]), and plants (brome mosaic virus [bmv]). however, the underlying mechanism is not fully understood. we have observed previously that in fhv and bmv, unlike ectopically expressed capsid protein (cp), packaging specificity results from rna encapsidation by cp that has been translated from mrna produced from replicating genomic rna. consequently, we hypothesize ...	2012	22438552
an examination of the electrostatic interactions between the n-terminal tail of the brome mosaic virus coat protein and encapsidated rnas.	the coat protein of positive-stranded rna viruses often contains a positively charged tail that extends toward the center of the capsid and interacts with the viral genome. electrostatic interaction between the tail and the rna has been postulated as a major force in virus assembly and stabilization. the goal of this work is to examine the correlation between electrostatic interaction and amount of rna packaged in the tripartite brome mosaic virus (bmv). nanoindentation experiment using atomic f ...	2012	22472420
chemical reactivity of brome mosaic virus capsid protein.	viral particles are biological machines that have evolved to package, protect, and deliver the viral genome into the host via regulated conformational changes of virions. we have developed a procedure to modify lysine residues with s-methylthioacetimidate across the ph range from 5.5 to 8.5. lysine residues that are not completely modified are involved in tertiary or quaternary structural interactions, and their extent of modification can be quantified as a function of ph. this procedure was app ...	2012	22750573
in vitro quantification of the relative packaging efficiencies of single-stranded rna molecules by viral capsid protein.	while most t=3 single-stranded rna (ssrna) viruses package in vivo about 3,000 nucleotides (nt), in vitro experiments have demonstrated that a broad range of rna lengths can be packaged. under the right solution conditions, for example, cowpea chlorotic mottle virus (ccmv) capsid protein (cp) has been shown to package rna molecules whose lengths range from 100 to 10,000 nt. furthermore, in each case it can package the rna completely, as long as the mass ratio of cp to nucleic acid in the assembl ...	2012	22951822
guanylylation-competent replication proteins of tomato mosaic virus are disulfide-linked.	the 130-kda and 180-kda replication proteins of tomato mosaic virus (tomv) covalently bind guanylate and transfer it to the 5' end of rna to form a cap. we found that guanylylation-competent tomv replication proteins are in membrane-bound, disulfide-linked complexes. guanylylation-competent replication proteins of brome mosaic virus and cucumber mosaic virus behaved similarly. to investigate the roles of disulfide bonding in the functioning of tomv replication proteins, each of the 19 cysteine r ...	2012	23062762
mutations in the coat protein-binding cis-acting rna motifs debilitate rna recombination of brome mosaic virus.	we have previously described the efficient homologous recombination system between 5' subgenomic rna3a (sgrna3a) and genomic rna3 of brome mosaic virus (bmv) in barley protoplasts (sztuba-solińska et al., 2011a). here, we demonstrated that sequence alterations in the coat protein (cp)-binding cis-acting rna motifs, the bbox region (in the intercistronic rna3 sequence) and the rna3 packaging element (pe, in the movement protein orf), reduced crossover frequencies in protoplasts. additionally, the ...	2012	23079110
functions of rice nac transcriptional factors, onac122 and onac131, in defense responses against magnaporthe grisea.	nac (nam/ataf/cuc) transcription factors have important functions in regulating plant growth, development, and abiotic and biotic stress responses. here, we characterized two rice pathogen-responsive nac transcription factors, onac122 and onac131. we determined that these proteins localized to the nucleus when expressed ectopically and had transcriptional activation activities. onac122 and onac131 expression was induced after infection by magnaporthe grisea, the causal agent of rice blast diseas ...	2013	23103994
low recombination activity of r region located at both ends of the hiv-1 genome.	although two strand transfer events are indispensable for the synthesis of double-stranded dna and establishing hiv-1 infection, the molecular basis of these phenomena is still unclear. the first obligatory template switching event occurs just at the beginning of the virus replication cycle and involves two copies of the 97-nucleotide long r region, located one each at the both ends of the hiv-1 genome (hiv-1 r). thus, one can expect that the molecular mechanism of this process is similar to the ...	2012	23130355
systemic transport of alfalfa mosaic virus can be mediated by the movement proteins of several viruses assigned to five genera of the 30k family.	we previously showed that the movement protein (mp) gene of alfalfa mosaic virus (amv) is functionally exchangeable for the cell-to-cell transport of the corresponding genes of tobacco mosaic virus (tmv), brome mosaic virus, prunus necrotic ringspot virus, cucumber mosaic virus and cowpea mosaic virus. we have analysed the capacity of the heterologous mps to systemically transport the corresponding chimeric amv genome. all mps were competent in systemic transport but required the fusion at their ...	2013	23136366
viral nanoparticles for in vivo tumor imaging.	the use of nanomaterials has the potential to revolutionize materials science and medicine. currently, a number of different nanoparticles are being investigated for applications in imaging and therapy. viral nanoparticles (vnps) derived from plants can be regarded as self-assembled bionanomaterials with defined sizes and shapes. plant viruses under investigation in the steinmetz lab include icosahedral particles formed by cowpea mosaic virus (cpmv) and brome mosaic virus (bmv), both of which ar ...	2012	23183850
utilizing virus-induced gene silencing for the functional characterization of maize genes during infection with the fungal pathogen ustilago maydis.	while in dicotyledonous plants virus-induced gene silencing (vigs) is well established to study plant-pathogen interaction, in monocots only few examples of efficient vigs have been reported so far. one of the available systems is based on the brome mosaic virus (bmv) which allows gene silencing in different cereals including barley (hordeum vulgare), wheat (triticum aestivum), and maize (zea mays).infection of maize plants by the corn smut fungus ustilago maydis leads to the formation of large ...	2013	23386294
analysis of the solvent accessibility of cysteine residues on maize rayado fino virus virus-like particles produced in nicotiana benthamiana plants and cross-linking of peptides to vlps.	mimicking and exploiting virus properties and physicochemical and physical characteristics holds promise to provide solutions to some of the world's most pressing challenges. the sheer range and types of viruses coupled with their intriguing properties potentially give endless opportunities for applications in virus-based technologies. viruses have the ability to self- assemble into particles with discrete shape and size, specificity of symmetry, polyvalence, and stable properties under a wide r ...	2013	23439009