polystyrene derivatives substituted with arginine interact with babanki (togaviridae) and kedougou (flaviviridae) viruses.outbreaks of new or old diseases appear primarily in tropical zones such as africa, south and central america, or asia. among these diseases, those induced by arboviruses (the best known of which are being yellow fever, dengue, ebola, and sindbis) are under intensive observation by the world health organization. rapid isolation and identification of the viral species is the first step in the diagnosis, study, and control of epidemics. one major problem with the isolation of viruses is capturing ...200312601758
functional nmda receptor channels generated by nmdar2b gene transfer in rat cerebellar purkinje cells.the adult cerebellar purkinje cell is an exceptional neuron in the central nervous system in that it expresses high levels of nmdar1 (nr1) mrna without expressing any nmdar2 (nr2) mrnas. it has no functional nmda receptor (nmdar) channels, although it receives enormous numbers of excitatory inputs. despite the high level of nr1 mrna expression, the presence and localization of nr1 protein in mature purkinje cells are controversial. to examine the presence of nr1 protein and its ability to form f ...200312603279
induction of apoptosis by paramyxovirus simian virus 5 lacking a small hydrophobic gene.simian virus 5 (sv5) is a member of the paramyxovirus family, which includes emerging viruses such as hendra virus and nipah virus as well as many important human and animal pathogens that have been known for years. sv5 encodes eight known viral proteins, including a small hydrophobic integral membrane protein (sh) of 44 amino acids. sv5 without the sh gene (rsv5deltash) is viable, and growth of rsv5deltash in tissue culture cells and viral protein and mrna production in rsv5deltash-infected cel ...200312610112
interactions between the transmembrane segments of the alphavirus e1 and e2 proteins play a role in virus budding and fusion.the alphavirus envelope is built by heterodimers of the membrane proteins e1 and e2. the complex is formed as a p62e1 precursor in the endoplasmic reticulum. during transit to the plasma membrane (pm), it is cleaved into mature e1-e2 heterodimers, which are oligomerized into trimeric complexes, so-called spikes that bind both to each other and, at the pm, also to nucleocapsid (nc) structures under the membrane. these interactions drive the budding of new virus particles from the cell surface. th ...200312610119
the 5'-end sequence of the genome of aichi virus, a picornavirus, contains an element critical for viral rna encapsidation.picornavirus positive-strand rnas are selectively encapsidated despite the coexistence of viral negative-strand rnas and cellular rnas in infected cells. however, the precise mechanism of the rna encapsidation process in picornaviruses remains unclear. here we report the first identification of an rna element critical for encapsidation in picornaviruses. the 5' end of the genome of aichi virus, a member of the family picornaviridae, folds into three stem-loop structures (sl-a, sl-b, and sl-c, fr ...200312610129
alphavirus vectors as tools in cancer gene therapy.alphavirus vectors, particularly those based on the replicon of semliki forest virus, have shown great potential as gene delivery vehicles for various applications in cancer gene therapy. the rapid production of high-titer recombinant sfv particles, which show impressive transduction rates in various mammalian cell lines, primary cultures and in vivo, results in high levels of transgene expression. additionally, sfv vectors induce apoptosis in transduced host cells, which can further increase th ...200212614181
experience strengthening transmission by driving ampa receptors into synapses.the mechanisms underlying experience-dependent plasticity in the brain may depend on the ampa subclass of glutamate receptors (ampa-rs). we examined the trafficking of ampa-rs into synapses in the developing rat barrel cortex. in vivo gene delivery was combined with in vitro recordings to show that experience drives recombinant glur1, an ampa-r subunit, into synapses formed between layer 4 and layer 2/3 neurons. moreover, expression of the glur1 cytoplasmic tail, a construct that inhibits synapt ...200312624270
facilitation of dendritic mrna transport by neurons, the proteins derived from mrnas localized in dendrites have been implicated in synaptic plasticity. the cytoplasmic polyadenylation element (cpe), a cis element in the 3'-utrs of specific dendritic mrnas, promotes cytoplasmic polyadenylation-induced translation in response to synaptic stimulation. here, we demonstrate that the cpe and its binding protein cpeb facilitate mrna transport to dendrites. in rat hippocampal neurons infected with recombinant viruses, the cpe is sufficient to ...200312629046
american genotype structures decrease dengue virus output from human monocytes and dendritic cells.the dengue virus type 2 structures probably involved in human virulence were previously defined by sequencing the complete genome of both american and southeast (se) asian genotype templates in patient serum (k. c. leitmeyer et al., j. virol. 73:4738-4747, 1999). we have now evaluated the effects of introducing a mutation in the envelope glycoprotein (e) gene and/or replacement of 5'- and 3'-nontranslated regions on dengue virus replication in human primary cell cultures. a series of chimeric in ...200312634353
hepatitis c virus glycoproteins interact with dc-sign and dc-signr.dc-sign and dc-signr are two closely related membrane-associated c-type lectins that bind human immunodeficiency virus (hiv) envelope glycoprotein with high affinity. binding of hiv to cells expressing dc-sign or dc-signr can enhance the efficiency of infection of cells coexpressing the specific hiv receptors. dc-sign is expressed on some dendritic cells, while dc-signr is localized to certain endothelial cell populations, including hepatic sinusoidal endothelial cells. we found that soluble ver ...200312634366
the abundant nuclear enzyme parp participates in the life cycle of simian virus 40 and is stimulated by minor capsid protein vp3.the abundant nuclear enzyme poly(adp-ribose) polymerase (parp) functions in dna damage surveillance and repair and at the decision between apoptosis and necrosis. here we show that parp binds to simian virus 40 (sv40) capsid proteins vp1 and vp3. furthermore, its enzymatic activity is stimulated by vp3 but not by vp1. experiments with purified mutant proteins demonstrated that the parp binding domain in vp3 is localized to the 35 carboxy-terminal amino acids, while a larger peptide of 49 amino a ...200312634384
engineering the transmissible gastroenteritis virus genome as an expression vector inducing lactogenic immunity.the genome of the coronavirus transmissible gastroenteritis virus (tgev) has been engineered as an expression vector with an infectious cdna. the vector led to the efficient (>40 micro g/10(6) cells) and stable (>20 passages) expression of a heterologous gene (green fluorescent protein [gfp]), driven by the transcription-regulating sequences (trs) of open reading frame (orf) 3a inserted in the site previously occupied by the nonessential orfs 3a and 3b. expression levels driven by this trs were ...200312634392
diverse dengue type 2 virus populations contain recombinant and both parental viruses in a single mosquito host.envelope (e) protein genes sampled from populations of dengue 2 (den-2) virus in individual aedes aegypti mosquitoes and in serum from dengue patients were copied to cdna, cloned, and sequenced. the nucleotide sequences of the e genes in more than 70% of the clones differed from the consensus sequence for the corresponding virus population at up to 11 sites, and 24 of the 94 clones contained at least one stop codon. virus populations recovered up to 2 years apart yielded clones with similar poly ...200312634407
development of an orally infectious sindbis virus transducing system that efficiently disseminates and expresses green fluorescent protein in aedes aegypti.we have constructed an orally infectious sindbis virus, me2/5'2j/gfp, that expresses green fluorescent protein (gfp) in the midgut of aedes aegypti and in other tissues as the virus disseminates. this virus has two unique features that are improvements over the sin-based expression systems currently used in mosquitoes. first, a subgenomic rna promoter and gfp coding sequence is located 5'- to the second subgenomic promoter and structural genes of the virus. second, the e2 glycoprotein gene of te ...200312653932
foamy virus envelope glycoprotein-mediated entry involves a ph-dependent fusion general, enveloped viruses use two different entry strategies and are classified accordingly into ph-dependent and ph-independent viruses. different members of the retrovirus family use one or the other strategy. little is known about the uptake of foamy viruses (fv), a special group of retroviruses, into the target cells. in this study, we examined the ph dependence of fv entry by analyzing fv envelope glycoprotein (env)-mediated infection of target cells with murine leukemia virus or fv vec ...200312663779
kinetics of cd4+ and cd8+ memory t-cell responses during hepatitis c virus rechallenge of previously recovered chimpanzees.the immunological correlates of hepatitis c virus (hcv)-specific immunity are not well understood. antibodies to hcv structural proteins do not appear to play a key role in clearance of the virus and do not persist after recovery. here, we studied the kinetics of the cellular immune responses of three hcv-recovered chimpanzees during rechallenge with increasing doses of homologous hcv. although hcv envelope antibodies remained undetectable throughout the rechallenge, all animals mounted rapid hc ...200312663785
complexes of poliovirus serotypes with their common cellular receptor, cd155.structures of all three poliovirus (pv) serotypes (pv1, pv2, and pv3) complexed with their cellular receptor, pv receptor (pvr or cd155), were determined by cryoelectron microscopy. both glycosylated and fully deglycosylated cd155 exhibited similar binding sites and orientations in the viral canyon for all three pv serotypes, showing that all three serotypes use a common mechanism for cell entry. difference maps between the glycosylated and deglycosylated cd155 complexes determined the sites of ...200312663789
morphological variants of sindbis virus produced by a mutation in the capsid protein.sindbis virus is a complex aggregate of rna, protein and lipid. the virus is organized as two nested t = 4 icosahedral protein shells between which is sandwiched a lipid bilayer. the virus rna resides within the inner protein shell. the inner protein shell is attached to the outer protein shell through contacts to proteins in the outer shell, which penetrate the lipid bilayer. the data presented in the following manuscript show that mutations in the capsid protein can result in the assembly of t ...200312667814
bak alters neuronal excitability and can switch from anti- to pro-death function during postnatal development.bak is a pro-apoptotic bcl-2 family protein that localizes to mitochondria. here we evaluate the function of bak in several mouse models of neuronal injury including neuronotropic sindbis virus infection, parkinson's disease, ischemia/stroke, and seizure. bak promotes or inhibits neuronal death depending on the specific death stimulus, neuron subtype, and stage of postnatal development. bak protects neurons from excitotoxicity and virus infection in the hippocampus. as mice mature, bak is conver ...200312689595
attenuated salmonella enterica serovar typhi and shigella flexneri 2a strains mucosally deliver dna vaccines encoding measles virus hemagglutinin, inducing specific immune responses and protection in cotton rats.measles remains a leading cause of child mortality in developing countries. residual maternal measles antibodies and immunologic immaturity dampen immunogenicity of the current vaccine in young infants. because cotton rat respiratory tract is susceptible to measles virus (mv) replication after intranasal (i.n.) challenge, this model can be used to assess the efficacy of mv vaccines. pursuing a new measles vaccine strategy that might be effective in young infants, we used attenuated salmonella en ...200312692223
luciferase imaging of a neurotropic viral infection in intact animals.the identification of viral determinants of virulence and host determinants of susceptibility to virus-induced disease is essential for understanding the pathogenesis of infection. obtaining this information requires infecting large numbers of animals to assay amounts of virus in a variety of organs and to observe the onset and progression of disease. as an alternative approach, we have used a murine model of viral encephalitis and an in vivo imaging system that can detect light generated by luc ...200312692235
human rhinovirus type 2 is internalized by clathrin-mediated endocytosis.using several approaches, we investigated the importance of clathrin-mediated endocytosis in the uptake of human rhinovirus serotype 2 (hrv2). by means of confocal immunofluorescence microscopy, we show that k(+) depletion strongly reduces hrv2 internalization. viral uptake was also substantially reduced by extraction of cholesterol from the plasma membrane with methyl-beta-cyclodextrin, which can inhibit clathrin-mediated endocytosis. in accordance with these data, overexpression of dynamin k44 ...200312692238
immunoregulation of a viral model of multiple sclerosis using the synthetic cannabinoid r+win55,212.theiler murine encephalomyelitis virus-induced demyelinating disease (tmev-idd) is a mouse model of chronic-progressive multiple sclerosis (ms) characterized by th1-mediated cns demyelination and spastic hindlimb paralysis. existing ms therapies reduce relapse rates in 30% of relapsing-remitting ms patients, but are ineffective in chronic-progressive disease, and their effects on disability progression are unclear. experimental studies demonstrate cannabinoids are useful for symptomatic treatmen ...200312697742
modified apoptotic molecule (bid) reduces hepatitis c virus infection in mice with chimeric human livers.hepatitis c virus (hcv) encodes a polyprotein consisting of core, envelope (e1, e2, p7), and nonstructural polypeptides (ns2, ns3, ns4a, ns4b, ns5a, ns5b). the serine protease (ns3/ns4a), helicase (ns3), and polymerase (ns5b) constitute valid targets for antiviral therapy. we engineered bh3 interacting domain death agonist (bid), an apoptosis-inducing molecule, to contain a specific cleavage site recognized by the ns3/ns4a protease. cleavage of the bid precursor molecule by the viral protease ac ...200312704395
genetic screen for monitoring hepatitis c virus ns3 serine protease activity.we have developed a genetic system to monitor the activity of the hepatitis c virus (hcv) ns3 serine protease. this genetic system is based on the bacteriophage lambda regulatory circuit where the viral repressor ci is specifically cleaved to initiate the switch from lysogeny to lytic infection. an hcv protease-specific target, ns5a-5b, was inserted into the lambda phage ci repressor. the target specificity of the hcv ns5a-5b repressor was evaluated by coexpression of this repressor with a beta- ...200312709356
the prevalence of antibodies against sindbis-related (pogosta) virus in different parts of study the occurrence of sindbis-related (pogosta) disease in finland by serological means.200312709538
effects of collagen matrix on sindbis virus infection of bhk cells.the effects of extracellular matrix (ecm) components on the outcomes of alphavirus interaction with cells are not known. studies that address such interactions have to address several methodological difficulties, including: the survival of the cells within the matrix; the passage of the virus through the matrix to infect embedded cells; and the dissociation of cells and matrix into single-cell suspension, before and after virus infection, for quantitative analysis. herein, these issues were addr ...200312711058
sindbis virus vectors designed to express a foreign protein as a cleavable component of the viral structural polyprotein.alphavirus-based expression vectors commonly use a duplicated 26s promoter to drive expression of a foreign gene. here we describe an expression strategy in which the foreign sequences are linked to the gene encoding the 2a protease of foot-and-mouth disease virus and then inserted in frame between the capsid and e3 genes of sindbis virus. during replication, the 2a fusion protein is synthesized as a component of the viral structural polyprotein that is then released by intramolecular cleavages ...200312719552
effect of p38 mitogen-activated protein kinase on the replication of encephalomyocarditis virus.cellular phosphorylation events during viral infection are necessary for effective viral replication. encephalomyocarditis (emc) virus has been used for studies on the molecular mechanisms of viral replication, but little is known about the cellular signaling pathways involved. this investigation was initiated to determine whether mitogen-activated protein kinases (mapks), which are central components of signal transduction pathways in the regulation of cell proliferation, play a role in the rep ...200312719557
vesicular stomatitis viruses with rearranged genomes have altered invasiveness and neuropathogenesis in mice.transcription of vesicular stomatitis virus is controlled by the position of a gene relative to the single 3' genomic promoter: promoter-proximal genes are transcribed at higher levels than those in more 5' distal positions. in previous work, we generated viruses having rearranged gene orders. these viruses had the promoter-proximal gene that encodes the nucleocapsid protein, n, moved to the second or fourth position in the genome in combination with the glycoprotein gene, g, moved from its usua ...200312719567
human immunodeficiency virus type 1 envelope-mediated neuropathogenesis: targeted gene delivery by a sindbis virus expression vector.sindbis virus (sin) expression vectors offer the opportunity for studying neuropathogenesis because of their distinct neural cell tropism. here, we demonstrate that a recombinant sin vector expressing egfp (sinrep5-egfp) infected multiple cell types including neural cells from several species relevant to lentivirus pathogenesis with high levels of transgene expression. infection of human neurons by a recombinant sin (sinrep5-jrfl) expressing the full-length envelope from a neurovirulent human im ...200312726727
activation of fusion by the ser virus f protein: a low-ph-dependent paramyxovirus entry process.ser virus, a paramyxovirus closely related to simian virus 5, induces no syncytium formation. the ser virus f protein has a long cytoplasmic tail (ct), and truncation or mutations of the ct result in enhanced syncytium formation (s. seth, a. vincent, and r. w. compans, j. virol. 77:167-178, 2003; s. tong, m. li, a. vincent, r. w. compans, e. fritsch, r. beier, c. klenk, m. ohuchi, and h.-d. klenk, virology 301:322-333, 2002). we hypothesized that the presence of the long ct serves to stabilize t ...200312743308
prevalence of sindbis-related (pogosta) virus infections in patients with determine the role of pogosta virus as a triggering infection in non-specific arthritis.200312747277
[complete nucleotide sequence of the nonstructural gene of alphavirus yn87448 strain isolated in china and its relationship to other sindbis viruses].to determine the complete nucleotide sequence of the nonstructural gene of yn87448 virus stain which was firstly isolated from a female patient with fever in yunnan province in 1986, and identified as a member of alphavirus by the serological method.199912759966
hepatitis c virus glycoproteins mediate ph-dependent cell entry of pseudotyped retroviral pseudotypes bearing native hepatitis c virus (hcv) glycoproteins (strain h and con1) are infectious for the human hepatoma cell lines huh-7 and plc/pr5. infectivity depends on coexpression of both e1 and e2 glycoproteins, is ph-dependent, and can be neutralized by mabs mapping to amino acids 412-447 within e2. cell-surface expression of one or all of the candidate receptor molecules (cd81, low-density lipoprotein receptor, scavenger receptor class b type 1, and dendritic cell-specific interc ...200312761383
flavivirus capsid is a dimeric alpha-helical protein.the capsid proteins of two flaviviruses, yellow fever virus and dengue virus, were expressed in escherichia coli and purified to near homogeneity suitable for biochemical characterization and structure determination by nuclear magnetic resonance. the oligomeric properties of the capsid protein in solution were investigated. in the absence of nucleic acid, both proteins were predominantly dimeric in solution. further analysis of both proteins with far-uv circular dichroism spectroscopy indicated ...200312768036
structures of immature flavivirus particles.structures of prm-containing dengue and yellow fever virus particles were determined to 16 and 25 a resolution, respectively, by cryoelectron microscopy and image reconstruction techniques. the closely similar structures show 60 icosahedrally organized trimeric spikes on the particle surface. each spike consists of three prm:e heterodimers, where e is an envelope glycoprotein and prm is the precursor to the membrane protein m. the pre-peptide components of the prm proteins in each spike cover th ...200312773377
transduction of dominant negative atf-1 suppresses the px gene expression in joint fibroblastic cells derived from htlv-i transgenic (p40tax) encoded by the env-px gene of human t-cell leukemia virus type i (htlv-i) interacts with cyclic adenosine-3',5'-monophosphate response element binding protein/activation transcription factor 1 (creb/atf-1) transcription factors of host cells and activates the viral long terminal repeat (ltr) promoter. this molecular interaction induces augmentation of viral gene expression and may result in development of htlv-i-associated diseases, including adult t-cell leukemia, htlv-i associated ...200312782019
assessing the feasibility of using neural precursor cells and peripheral blood mononuclear cells for detection of bioactive sindbis virus.viruses form a significant class of bio-threat agents. currently, the only method to determine the bioactivity of viruses in vitro is to measure viral and cellular responses after co-incubation of cells with virus. our goal is to find biomarkers for classification of agents, establishment of bioactivity, and/or prediction of disease outcomes. to begin development of a cell-based biosensor for detection of bioactive sindbis virus (sv), our model analyte, we surveyed the outcomes of sv interaction ...200312782470
murine cytomegalovirus abortively infects human dendritic cells, leading to expression and presentation of virally vectored genes.dendritic cells (dc) are potent antigen-presenting cells that play a crucial role in antigen-specific immune responses. thus, the targeting of exogenous antigens to dc has become a popular approach for cancer immunotherapy and vaccine development. in this report, we studied the interplay between murine cytomegalovirus (mcmv) and human monocyte-derived dc. the results showed that an enhanced green fluorescent protein (egfp)-encoding, replication-competent mcmv vector underwent abortive infection ...200312805417
common host genes are activated in mouse brain by japanese encephalitis and rabies viruses.this study identified nine genes whose expression is upregulated in the central nervous system (cns) of mice during japanese encephalitis virus (jev) infection. these include: cathepsin s, oligoadenylate synthetase (oas), garg49/irg2, lymphocyte antigen-6a (ly-6a), macrophage activation gene-2 (mpa2), early growth response gene1 (egr1), pyrimidine 5'-nucleotidase (p5n), apolipoprotein d (apod) and stat1. activation of all nine genes during jev infection was confirmed by northern blot analysis. j ...200312810866
disc1 (disrupted-in-schizophrenia 1) is a centrosome-associated protein that interacts with map1a, mipt3, atf4/5 and nudel: regulation and loss of interaction with mutation.disrupted-in-schizophrenia 1 (disc1) is a novel gene associated with schizophrenia by multiple genetic studies. in order to determine how mutations in disc1 might cause susceptibility to schizophrenia, we undertook a comprehensive study of the cellular biology of disc1 in its full-length and disease-associated mutant forms. disc1 interacts by yeast two-hybrid, mammalian two-hybrid, and co-immunoprecipitation assays with multiple proteins of the centrosome and cytoskeletal system, including mipt3 ...200312812986
use of a sindbis virus dna-based expression vector for induction of protective immunity against pseudorabies virus in pigs.injection of plasmid dna encoding pseudorabies virus (prv) glycoproteins into pig muscle has been shown to result in protective immunity against lethal infection. nevertheless, such dna vaccines are still less efficient than some attenuated or killed live vaccines. one way to increase dna vaccine efficacy is to improve the vectorisation system at the molecular level, thereby enhancing the rate of in vivo-produced immunogen protein and consequently specific acquired immunity. the present study co ...200312814698
possible involvement of rap1 and ras in glutamatergic synaptic transmission.rap1a, first identified as a suppressor of transformed phenotype induced by an activated ras oncogene, is abundantly expressed in the brain. its neurophysiological function, however, is poorly understood. when an activated rap1a mutant (rap1-12v) or a dominant negative h-ras mutant (ras-17n) was expressed in ca1 neurons in cultured hippocampal slices using the sindbis virus-mediated gene transfer technique, nmda receptor current in response to schaffer collateral stimulation was suppressed. expr ...200312824760
nonstructural protein precursor ns4a/b from hepatitis c virus alters function and ultrastructure of host secretory apparatus.the nonstructural proteins of hepatitis c virus (hcv) have been shown previously to localize to the endoplasmic reticulum (er) when expressed singly or in the context of other hcv proteins. to determine whether the expression of hcv nonstructural proteins alters er function, we tested the effect of expression of ns2/3/4a, ns4a, ns4b, ns4a/b, ns4b/5a, ns5a, and ns5b from genotype 1b hcv on anterograde traffic from the er to the golgi apparatus. only the nominal precursor protein ns4a/b affected t ...200312829824
fitness of a turnip crinkle virus satellite rna correlates with a sequence-nonspecific hairpin and flanking sequences that enhance replication and repress the accumulation of virions.satc, a satellite rna associated with turnip crinkle virus (tcv), enhances the ability of the virus to colonize plants by interfering with stable virion accumulation (f. zhang and a. e. simon, unpublished data). previous results suggested that the motif1-hairpin (m1h), a replication enhancer on minus strands, forms a plus-strand hairpin flanked by ca-rich sequence that may be involved in enhancing systemic infection (g. zhang and a. e. simon, j. mol. biol. 326:35-48, 2003). in this study, sequen ...200312829828
extensive immune-mediated hippocampal damage in mice surviving infection with neuroadapted sindbis virus.viral infections of the central nervous system and immune responses to these infections cause a variety of neurological diseases. infection of weanling mice with sindbis virus causes acute nonfatal encephalomyelitis followed by clearance of infectious virus, but persistence of viral rna. infection with a neuroadapted strain of sindbis virus (nsv) causes fatal encephalomyelitis, but passive transfer of immune serum after infection protects from fatal disease and infectious virus is cleared. to de ...200312832200
human embryonic germ cell derivatives facilitate motor recovery of rats with diffuse motor neuron injury.we have investigated the potential of human pluripotent cells to restore function in rats paralyzed with a virus-induced motor neuronopathy. cells derived from embryonic germ cells, termed embryoid body-derived (ebd) cells, introduced into the csf were distributed extensively over the rostrocaudal length of the spinal cord and migrated into the spinal cord parenchyma in paralyzed, but not uninjured, animals. some of the transplanted human cells expressed the neuroglial progenitor marker nestin, ...200312832537
a modified sindbis vector for prolonged gene expression in neurons.sindbis viruses have been widely used in neurobiology to express a variety of genes in cultured neurons, in cultured slices, and in vivo. they provide fast onset and high levels of expression of foreign genes, but the expression is limited to a short time window due to a shut-off of host protein synthesis. we have used a mutation in an essential gene (nsp2) of the life cycle of sindbis, which allows the functional analysis of changes in protein expression for >/=6 days after infection. this sind ...200312853440
a heterologous coiled coil can substitute for helix i of the sindbis virus capsid protein.alphavirus core assembly proceeds along an assembly pathway involving a dimeric assembly intermediate. several regions of the alphavirus capsid protein have been implicated in promoting and stabilizing this dimerization, including a putative heptad repeat sequence named helix i. this sequence, which spans residues 38 to 55 of the sindbis virus capsid protein, was implicated in stabilizing dimeric contacts initiated through the c-terminal two-thirds of the capsid protein and nucleic acid. the stu ...200312857904
complete genomic sequence of the australian south-west genotype of sindbis virus: comparisons with other sindbis strains and identification of a unique deletion in the 3'-untranslated region.our previous studies have shown that two distinct genotypes of sindbis (sin) virus occur in australia. one of these, the oriental/australian type, circulates throughout most of the australian continent, whereas the recently identified south-west (sw) genetic type appears to be restricted to a distinct geographic region located in the temperate south-west of australia. we have now determined the complete nucleotide and translated amino acid sequences of a sw isolate of sin virus (sw6562) and perf ...200312876458
adaptation of puumala hantavirus to cell culture is associated with point mutations in the coding region of the l segment and in the noncoding regions of the s segment.we previously developed a model for studies on hantavirus host adaptation and initiated genetic analysis of puumala virus variants passaged in colonized bank voles and in cultured vero e6 cells. with the data presented in this paper, the sequence comparison of the wild-type and vero e6-adapted variants of puumala virus, strain kazan, has been completed. the only amino acid substitution that distinguished the two virus variants was found in the l protein, ser versus phe at position 2053. another ...200312885898
deletions in the putative cell receptor-binding domain of sindbis virus strain mre16 e2 glycoprotein reduce midgut infectivity in aedes aegypti.the sindbis virus (alphavirus; togaviridae) strain mre16 efficiently infects aedes aegypti mosquitoes that ingest a blood meal containing 8 to 9 log(10) pfu of virus/ml. however, a small-plaque variant of this virus, mre16sp, poorly infects mosquitoes after oral infection with an equivalent titer. to determine the genetic differences between mre16 and mre16sp viruses, we have sequenced the mre16sp structural genes and found a 90-nucleotide deletion in the e2 glycoprotein that spans the 3' end of ...200312885905
reovirus-induced alteration in expression of apoptosis and dna repair genes with potential roles in viral pathogenesis.reoviruses are a leading model for understanding cellular mechanisms of virus-induced apoptosis. reoviruses induce apoptosis in multiple cell lines in vitro, and apoptosis plays a key role in virus-induced tissue injury of the heart and brain in vivo. the activation of transcription factors nf-kappab and c-jun are key events in reovirus-induced apoptosis, indicating that new gene expression is critical to this process. we used high-density oligonucleotide microarrays to analyze cellular transcri ...200312885910
characterization of the intracellular transport of glur1 and glur2 alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor subunits in hippocampal neurons.little is known about the dynamics of the dendritic transport of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (ampars) to synapses. here, using virally expressed green fluorescent protein (gfp)-glur1 and gfp-glur2 and confocal photobleach techniques we show near real-time movement of these subunits in living cultured hippocampal neurons. gfp-glur1 fluorescence was widely distributed throughout the extranuclear compartment with no evidence for discrete intracellular stores. ...200312909632
recombinant sindbis/venezuelan equine encephalitis virus is highly attenuated and immunogenic.venezuelan equine encephalitis virus (veev) is an important, naturally emerging zoonotic virus. veev was a significant human and equine pathogen for much of the past century, and recent outbreaks in venezuela and colombia (1995), with about 100,000 human cases, indicate that this virus still poses a serious public health threat. the live attenuated tc-83 vaccine strain of veev was developed in the 1960s using a traditional approach of serial passaging in tissue culture of the virulent trinidad d ...200312915543
complementation of a deletion in the rubella virus p150 nonstructural protein by the viral capsid protein.rubella virus (rub) replicons with an in-frame deletion of 507 nucleotides between two noti sites in the p150 nonstructural protein (deltanoti) do not replicate (as detected by expression of a reporter gene encoded by the replicon) but can be amplified by wild-type helper virus (tzeng et al., virology 289:63-73, 2001). surprisingly, virus with deltanoti was viable, and it was hypothesized that this was due to complementation of the noti deletion by one of the virion structural protein genes. int ...200312915564
low ph, caprylate incubation as a second viral inactivation step in the manufacture of albumin. parametric and validation studies.caprylate has long been used as a stabiliser for albumin solutions, as well as a precipitation agent for immunoglobulins, ceruloplasmin and more recently in removing contaminants during albumin purification. its virucidal properties have been explored and it has been proposed that the non-ionised form of the caprylate acid disrupts the integrity of the lipid bilayer and membrane associated proteins of enveloped viruses. the studies reported here further explore the use of this fatty acid to inac ...200312935811
antiviral effects of geranylgeranylacetone: enhancement of mxa expression and phosphorylation of pkr during influenza virus infection.a cyclic polyisoprenoid compound, geranylgeranylacetone (gga), has been used as antiulcer drug. gga is also a potent inducer of heat shock proteins (hsps). hsps are considered to induce an antiviral effect; however, the detailed mechanism is unknown. to determine whether gga might show antiviral activity and what the mechanism is, the effect of gga against influenza virus (strain pr8) infection in vivo and in vitro was investigated. the results demonstrated that gga treatment strongly suppressed ...200312936994
packaging of brome mosaic virus rna3 is mediated through a bipartite signal.the three genomic and a single subgenomic rna of brome mosaic virus (bmv), an rna virus infecting plants, are packaged by a single-coat protein (cp) into three morphologically indistinguishable icosahedral virions with t = 3 quasi-symmetry. genomic rnas 1 and 2 are packaged individually into separate particles whereas genomic rna3 and subgenomic rna4 (coat protein mrna) are copackaged into a single particle. we report here that packaging of dicistronic rna3 requires a bipartite signal. a highly ...200312941883
cis-acting elements required for efficient packaging of brome mosaic virus rna3 in barley protoplasts.brome mosaic virus (bmv) is a positive-sense rna plant virus, the tripartite genomic rnas of which are separately packaged into virions. rna3 is copackaged with subgenomic rna4. in barley protoplasts coinoculated with rna1 and rna2, an rna3 mutant with a 69-nucleotide (nt) deletion in the 3'-proximal region of the 3a open reading frame (orf) was very poorly packaged compared with other rna3 mutants and wild-type rna3, despite their comparable accumulation in the absence of coat protein. computer ...200312941908
t cells cause acute immunopathology and are required for long-term survival in mouse adenovirus type 1-induced encephalomyelitis.infection of adult c57bl/6 (b6) mice with mouse adenovirus type 1 (mav-1) results in dose-dependent encephalomyelitis. utilizing immunodeficient mice, we analyzed the roles of t cells, t-cell subsets, and t-cell-related functions in mav-1-induced encephalomyelitis. t cells, major histocompatibility complex (mhc) class i, and perforin contributed to acute disease signs at 8 days postinfection (p.i.). acute mav-1-induced encephalomyelitis was absent in mice lacking t cells and in mice lacking perf ...200312941916
synthesis, antiviral and cytotoxic activity of 6-bromo-2,3-disubstituted-4(3h) the present study, a series of 6-bromo-2,3-disubstitued-4(3h)-quinazolinones was synthesized by condensation of 6-bromo-2-substituted-benzoxazin-4-one with trimethoprim, pyrimethamine and lamotrigine. the chemical structures of the synthesized compounds were confirmed by means of ir, (1)h-nmr and mass spectral and elemental analysis. the antiviral activity and cytotoxicity of the compounds were tested in e(6)sm (herpes simplex-1 kos, herpes simplex-1 tk-kos acv, herpes simplex-2 g, vaccinia v ...200312951471
an alphavirus replicon particle chimera derived from venezuelan equine encephalitis and sindbis viruses is a potent gene-based vaccine delivery vector.alphavirus replicon particle-based vaccine vectors derived from sindbis virus (sin), semliki forest virus, and venezuelan equine encephalitis virus (vee) have been shown to induce robust antigen-specific cellular, humoral, and mucosal immune responses in many animal models of infectious disease and cancer. however, since little is known about the relative potencies among these different vectors, we compared the immunogenicity of replicon particle vectors derived from two very different parental ...200312970424
glycoprotein of nonpathogenic rabies viruses is a key determinant of human cell apoptosis.we showed that, unlike pathogenic rabies virus (rv) strain cvs, attenuated rv strain era triggers the caspase-dependent apoptosis of human cells. furthermore, we observed that the induction of apoptosis is correlated with a particular virus antigen distribution: the overexpression of the viral g protein on the cell surface, with continuous localization on the cytoplasmic membrane, and large cytoplasmic inclusions of the n protein. to determine whether one of these two major rv proteins (g and n ...200312970438
sindbis virus: a newly recognized arthropodtransmitted virus. 195513259009
tissue culture applied to the study of sindbis virus. 195513259010
studies of the sindbis virus. i. susceptibility of the cave bat by various routes or exposure. 195613381878
studies of the sindbis virus. ii. susceptibility of the suckling hamster by various routes or exposure. 195613381879
electron microscope studies of sindbis virus: a newly recognized arthropod-transmitted virus. 195713403125
zic2 patterns binocular vision by specifying the uncrossed retinal projection.during cns development, combinatorial expression of transcription factors controls neuronal subtype identity and subsequent axonal trajectory. regulatory genes designating the routing of retinal ganglion cell (rgc) axons at the optic chiasm to the appropriate hemisphere, a pattern critical for proper binocular vision, have not been identified. here, we show that the zinc finger transcription factor zic2, a vertebrate homolog of the drosophila gene odd-paired, is expressed in rgcs with an uncross ...200313678579
serological evidence of west nile virus, usutu virus and sindbis virus infection of birds in the uk.the introduction and rapid dispersal of the african flavivirus west nile virus (wnv) throughout north america, and the high fatality rate due to encephalitis in birds, horses, other wildlife species and humans, has attracted major attention worldwide. usutu virus, another flavivirus, came to prominence in 2001, when it was identified as the agent responsible for a drop in the bird population in austria; previously this encephalitic virus was found only in birds and mosquitoes in africa. sindbis ...200313679615
alteration of cellular resistance to sindbis virus in mixed cultures of human cells attributable to interferon. 196213901739
conditions for the production of an interferon appearing in chick cell cultures infected with sindbis virus. 196213907852
kinetic considerations of the inhibitory action of an interferon produced in chick cultures infected with sindbis virus. 196213907854
sindbis virus infection in man. report of a case with recovery of virus from skin lesions. 196313932506
enhancement of sindbis virus plaque size in cell cultures treated with mumps virus-infected egg fluid. 196313945847
protective effect of interferon in rats infected with sindbis virus. 196314027060
purification and partial chemical analysis of sindbis virus. 196314043407
the source of the ribonucleic acid and phospholipid of sindbis virus. 196314043408
precipitation and recovery of sindbis virus from solutions of low ionic strength. 196314070182
production of interferon by newborn and adult mice infected with sindbis virus. 196414166127
the origin of the protein of sindbis virus. 196414187910
inhibition by 3-methylcholanthrene of interferon formation in rat-embryo cells infected with sindbis virus. 196414191402
effects of polycyclic aromatic carcinogens on viral replication: similarity to actinomycin d.when incorporated into a nutrient overlay, the carcinogenic hydrocarbons benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene inhibit plaque formation by herpes virus and vaccinia virus, dna viruses, but not by sindbis virus, an rna virus. these carcinogens also decrease herpes and vaccinia virus yields in liquid medium, without affecting sindbis virus yields. four structurally related, but noncarcinogenic polycyclic hydrocarbons, namely benzo[e]pyrene, pyrene, benz[a]anthracene and anthracene, hav ...196414191704
[small plaque mutants of sindbis virus]. 196414229531
the isolation of sindbis virus from the mosquito mansonia (coquillettidia) fuscopennata (theobald) in uganda. 196414249017
occurrence of antibodies to sindbis virus in children from a west nile endemic area. 196514252806
transmission of sindbis virus by aedes aegypti to a chick embryo cell culture system. 196514264544
conditional-lethal mutants of an animal virus: identification of two cistrons.two different temperature-sensitive conditional-lethal mutants of sindbis virus, an animal virus that contains rna, have been isolated. when cultured in chick fibroblast monolayers at 42 degrees c, these mutants yield less than 0.05 percent as much virus as does the wild type, whereas at 27 degrees c they grow normally. one mutant appears to be altered in the synthesis of a protein that is produced early in the infection and is required for viral rna synthesis. the other mutant produces as much ...196514277837
virus invasion of the central nervous system: a study of sindbis virus infection in the mouse using fluorescent antibody. 196514328022
a strain of sindbis virus isolated from culex bitaeniorhynchus mosquitoes in the philippines. 196214495059
identification of a heparin-binding motif on adeno-associated virus type 2 capsids.infection of cells with adeno-associated virus (aav) type 2 (aav-2) is mediated by binding to heparan sulfate proteoglycan and can be competed by heparin. mutational analysis of aav-2 capsid proteins showed that a group of basic amino acids (arginines 484, 487, 585, and 588 and lysine 532) contribute to heparin and hela cell binding. these amino acids are positioned in three clusters at the threefold spike region of the aav-2 capsid. according to the recently resolved atomic structure for aav-2, ...200314512555
bioluminescence imaging reveals systemic dissemination of herpes simplex virus type 1 in the absence of interferon receptors.herpes simplex virus type 1 (hsv-1) can produce disseminated, systemic infection in neonates and patients with aids or other immunocompromising diseases, resulting in significant morbidity and mortality in spite of antiviral therapy. components of host immunity that normally limit hsv-1 to localized epithelial and neuronal infection remain incompletely defined. we used in vivo bioluminescence imaging to determine effects of type i and ii interferons (ifns) on replication and tropism of hsv-1 inf ...200314512556
the 5' untranslated region of alfalfa mosaic virus rna 1 is involved in negative-strand rna synthesis.the three genomic rnas of alfalfa mosaic virus each contain a unique 5' untranslated region (5' utr). replacement of the 5' utr of rna 1 by that of rna 2 or 3 yielded infectious replicons. the sequence of a putative 5' stem-loop structure in rna 1 was found to be required for negative-strand rna synthesis. a similar putative 5' stem-loop structure is present in rna 2 but not in rna 3.200314512577
inhibition of translation and induction of apoptosis by bunyaviral nonstructural proteins bearing sequence similarity to reaper.members of the california serogroup of bunyaviruses (family bunyaviridae) are the leading cause of pediatric viral encephalitis in north america. significant cell death is observed as part of the infection pathology. we now report that a bunyaviral nonstructural protein termed nss shows sequence similarity to reaper, a proapoptotic protein from drosophila. although nss proteins lack the reaper n-terminal motif critical for iap inhibition, they do retain other functions of reaper that map to cons ...200314517326
visualization of membrane protein domains by cryo-electron microscopy of dengue virus.improved technology for reconstructing cryo-electron microscopy (cryo-em) images has now made it possible to determine secondary structural features of membrane proteins in enveloped viruses. the structure of mature dengue virus particles was determined to a resolution of 9.5 a by cryo-em and image reconstruction techniques, establishing the secondary structural disposition of the 180 envelope (e) and 180 membrane (m) proteins in the lipid envelope. the alpha-helical 'stem' regions of the e mole ...200314528291
boosting with recombinant vaccinia increases hpv-16 e7-specific t cell precursor frequencies and antitumor effects of hpv-16 e7-expressing sindbis virus replicon particles.immunotherapy using the heterologous prime-boost regimen has emerged as an attractive approach for generating antigen-specific t-cell-mediated immune responses against tumors and infectious diseases. we have previously linked the mycobacterium tuberculosis heat-shock protein 70 (hsp70) to the hpv-16 e7 antigen creating a chimera, e7/hsp70. we found that nucleic acid vaccines encoding e7/hsp70 can generate strong antitumor immunity. recently, replication-defective sindbis virus replicon particle ...200314529828
antizyme frameshifting as a functional probe of eukaryotic translational termination.translation termination in eukaryotes is mediated by the release factors erf1 and erf3, but mechanisms of the interplay between these factors are not fully understood, due partly to the difficulty of measuring termination on eukaryotic mrnas. here, we describe an in vitro system for the assay of termination using competition with programmed frameshifting at the recoding signal of mammalian antizyme. the efficiency of antizyme frameshifting in rabbit reticulocyte lysates was reduced by addition o ...200314530443
bcl-xl/bcl-2 coordinately regulates apoptosis, cell cycle arrest and cell cycle entry.bcl-x(l) and bcl-2 inhibit both apoptosis and proliferation. in investigating the relationship between these two functions of bcl-x(l) and bcl-2, an analysis of 24 bcl-x(l) and bcl-2 mutant alleles, including substitutions at residue y28 previously reported to selectively abolish the cell cycle activity, showed that cell cycle delay and anti-apoptosis co-segregated in all cases. in determining whether bcl-2 and bcl-x(l) act in g(0) or g(1), forward scatter and pyronin y fluorescence measurements ...200314532118
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