Publications

specific inhibition of human immunodeficiency virus type 1 reverse transcriptase mediated by soulattrolide, a coumarin isolated from the latex of calophyllum teysmannii.	soulattrolide (1), a coumarin isolated from calophyllum teysmannii latex, was found to be a potent inhibitor of hiv-1 reverse transcriptase (rt) with an ic50 of 0.34 microm. inhibition was remarkably specific, with no appreciable activity being observed toward hiv-2 rt, amv rt, rna polymerase, or dna polymerases alpha or beta.	1996	8864237
a plant viral coat protein rna binding consensus sequence contains a crucial arginine.	a defining feature of alfalfa mosaic virus (amv) and ilarviruses [type virus: tobacco streak virus (tsv)] is that, in addition to genomic rnas, viral coat protein is required to establish infection in plants. amv and tsv coat proteins, which share little primary amino acid sequence identity, are functionally interchangeable in rna binding and initiation of infection. the lysine-rich amino-terminal rna binding domain of the amv coat protein lacks previously identified rna binding motifs. here, th ...	1996	8890181
alfalfa mosaic virus strains t6 and 425 differ in their capsid protein.	capsid proteins (cps) of two strains of alfalfa mosaic virus (aimv)-t6 and 425-were compared using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (sds-page) peptide mapping and two-dimensional page (2d-page). the cps had identical molecular mass but differed in their peptide pattern and charge. the aimv strain t6 was isolated from lucerne in czech republic (gallo, 1977). previously, its morhology, symptomatology and rna electrophoretic mobility were characterized and compared with th ...	1996	8891095
bent pseudoknots and novel rna inhibitors of type 1 human immunodeficiency virus (hiv-1) reverse transcriptase.	the reverse transcriptase (rt) of the human immunodeficiency virus (hiv) is a proven target for therapeutic intervention of hiv infections. we have found several new rna inhibitors of hiv-1 rt that differ significantly from the pseudoknot ligands found previously, along with a wide variety of pseudoknot variants. one pseudoknot variant and three novel ligands were studied in more detail. each specifically inhibits dna polymerization by hiv rt (half-maximal inhibition at 0.3 to 20 nm inhibitor), ...	1996	8980676
structural elements of the 3'-terminal coat protein binding site in alfalfa mosaic virus rnas.	the 3'-terminal of the three genomic rnas of alfalfa mosaic virus (aimv) and ilarviruses contain a number of augc-motifs separated by hairpin structures. binding of coat protein (cp) to such elements in the rnas is required to initiate infection of these viruses. determinants for cp binding in the 3'-terminal 39 nucleotides (nt) of aimv rna 3 were analyzed by band-shift assays. from the 5'- to 3'-end this 39 nt sequence contains augc-motif 3, stem-loop structure 2 (stlp2), augc-motif 2, stem-loo ...	1996	8758992
accumulation of alfalfa mosaic virus rnas 1 and 2 requires the encoded proteins in cis.	rnas 1 and 2 of the tripartite genome of alfalfa mosaic virus (a1mv) encode the replicase proteins p1 and p2, respectively. p1 expressed in transgenic plants (p1 plants) can be used in trans to support replication of a1mv rnas 2 and 3, and p2 expressed in transgenic plants (p2 plants) can be used in trans to support replication of a1mv rnas 1 and 3. wild-type rna 1 was able to coreplicate with rnas 2 and 3 in p1 plants, but this ability was abolished by frameshifts or deletions in the p1 gene of ...	1996	8764017
faetl motif required for leukemic transformation by v-myb.	the nuclear protein v-myb, encoded by the avian myeloblastosis virus (amv), can induce acute monoblastic leukemia in vivo and transform chicken myelomonocytic cells in culture. the n terminus of v-myb functions as the dna-binding domain, and multiple central and c-terminal regions of this protein have been reported to function in transcriptional activation of model reporter genes. we showed previously that a c-terminal domain (amino acids 296 to 371) is required for transcriptional activation an ...	1996	8764074
myb-induced transformation.	the c-myb protooncogene has been implicated in the development of avian and murine hematopoietic neoplasms of the myeloid and lymphoid lineages. the transcription factor encoded by this gene has a dual function in oncogenesis because it regulates genes that prevent apoptosis and genes involved in cellular proliferation. c-myb has repeatedly been a target of retroviral insertional mutagenesis. the most common mechanism by which retroviruses activate c-myb's oncogenic potential is by providing tra ...	1996	9258605
transgenic plantlets of 'chancellor' grapevine (vitis sp.) from biolistic transformation of embryogenic cell suspensions.	transgenic plantlets of 'chancellor' grapevine (vitis l. complex interspecific hybrid) were produced via biolistic transformation. embryogenic cell suspensions were bombarded with 1 μm tungsten particles coated with pbi426 which encodes a fusion peptide between β-glucuronidase (gus) and neomycin phosphotransferase ii (nptii). the fusion peptide is under the control of a double 35s cauliflower mosaic virus promoter and a leader sequence from alfalfa mosaic virus. the cells were placed on kanamyci ...	1996	24178348
c-myb in smooth muscle cells.	the proto-oncogene c-myb is a cellular homolog of a viral oncogene v-myb found in two independently derived avian acute leukemia viruses: avian myeloblastosis vn-us (amv) and e26 leukemia virus (1). the myb gene is highly conserved in eukaryotes, and it usually consists of 15 exons spanning over 35 kb of genomic dna (1).in humans, c-myb gene locus has been mapped to chromosome 6 (6q22-23) however, myb mrna expressed in thymus contains transcripts originating from chromosome 17 (17q25), suggestin ...	1996	21359720
tubule-forming capacity of the movement proteins of alfalfa mosaic virus and brome mosaic virus.	the structural phenotype of the movement proteins (mps) of two representatives of the bromoviridae, alfalfa mosaic virus (amv) and brome mosaic virus (bmv), was studied in protoplasts. immunofluorescence microscopy showed that the mps of these viruses, for which there has been no evidence of a tubule-guided mechanism, assemble into long tubular structures at the surface of the infected protoplast. electron microscopy and immunogold analysis confirmed the presence of both mp and virus particles i ...	1997	9267012
comparison of the role of 5' terminal sequences of alfalfa mosaic virus rnas 1, 2, and 3 in viral rna replication.	the 5' untranslated regions (utrs) of the genomic rnas 1, 2, and 3 of alfalfa mosaic virus (amv) are 100, 54, and 345 nucleotides (nt) long, respectively, and lack extensive sequence similarity to each other. rna 3 encodes the movement protein p3 and the coat protein and can be replicated in transgenic tobacco plants expressing the replicase proteins p1 and p2 (p12 plants). 5' cis-acting sequences involved in rna 3 replication have been shown to be confined to the 5' utr. when the 5' utr of rna ...	1997	9281513
synthesis of full-length potyvirus cdna copies suitable for the analysis of genome polymorphism.	new methods facilitating the synthesis and amplification of full-length cdna copies of single-stranded viral rna genomes have been developed. a method is described for the efficient purification of potyviral rna and total rna from infected plants and it is shown that they can serve as templates for the efficient synthesis of a full-length, 10 kb long, genomic cdna. two different reverse transcriptases were used (amv-rt and mmlv-rt); only the first reverse transcriptase produced a good quality, f ...	1997	9300384
the structure of alfalfa mosaic virus capsid protein assembled as a t=1 icosahedral particle at 4.0-a resolution.	k. fukuyama, s. s. abdel-meguid, j. e. johnson, and m. g. rossmann (j. mol. biol. 167:873-984, 1983) reported the structure of alfalfa mosaic virus assembled from the capsid protein as a t=1 icosahedral empty particle at 4.5-a resolution. the information contained in the structure included the particle size, protein shell thickness, presence of wide holes at the icosahedral fivefold axes, and a proposal that the capsid protein adopts a beta-barrel structure. in the present work, the x-ray diffra ...	1997	9311881
mutations in coat protein binding sites of alfalfa mosaic virus rna 3 affect subgenomic rna 4 accumulation and encapsidation of viral rnas.	the 3'-untranslated regions (3'-utrs) of the three rnas of alfalfa mosaic virus (amv) contain a specific binding site for coat protein (cp) and act as a promoter for minus-strand rna synthesis by the purified amv rna-dependent rna polymerase (rdrp) in an in vitro assay. binding of cp to the viral rnas is required to initiate infection. the sequence of the 3'-terminal 39 nucleotides of amv rna 3 can be folded into two stem-loop structures flanked by three single-stranded augc sequences and repres ...	1997	9343194
the complete nucleotide sequence of prune dwarf ilarvirus rna-1.	the sequence of prune dwarf ilarvirus (pdv) rna-1 has been determined; it consists of 3,374 nucleotides and contains a single open reading frame of 3,168 nucleotides. the putative translation product is 1,055 amino acids in length with a calculated molecular mass of 118.9 kda. both the nucleic acid and the translated amino acid sequences show stronger homology to the corresponding rna-1 and orf-1 of apple mosaic ilarvirus and alfalfa mosaic alfamovirus than to spinach latent mosaic ilarvirus or ...	1997	9672650
oncogenic point mutations induce altered conformation, redox sensitivity, and dna binding in the minimal dna binding domain of avian myeloblastosis virus v-myb.	c-myb is the founder member of a class of transcription factors with tryptophan-rich repeats responsible for dna binding. activated oncogenic forms of myb are encoded by the avian retroviruses, avian myeloblastosis virus (amv) and e26. amv v-myb encodes a truncated protein with 11 point mutations relative to c-myb. the mutations in the dna binding domain (dbd) were reported to impose distinct phenotypes of differentiation on transformed myeloid cells (introna, m., golay, j., frampton, j., nakano ...	1997	9020167
in vitro genetic selection analysis of alfalfa mosaic virus coat protein binding to 3'-terminal augc repeats in the viral rnas.	the coat proteins of alfalfa mosaic virus (amv) and the related ilarviruses bind specifically to the 3' untranslated regions of the viral rnas, which contain conserved repeats of the tetranucleotide sequence augc. the purpose of this study was to develop a more detailed understanding of rna sequence and/or structural determinants required for coat protein binding by characterizing the role of the augc repeats. starting with a complex pool of 39-nucleotide rna molecules containing random substitu ...	1997	9032367
functional equivalence of common and unique sequences in the 3' untranslated regions of alfalfa mosaic virus rnas 1, 2, and 3.	the 3' untranslated regions (utrs) of alfalfa mosaic virus (amv) rnas 1, 2, and 3 consist of a common 3'-terminal sequence of 145 nucleotides (nt) and upstream sequences of 18 to 34 nt that are unique for each rna. the common sequence can be folded into five stem-loop structures, a to e, despite the occurrence of 22 nt differences between the three rnas in this region. exchange of the common sequences or full-length utrs between the three genomic rnas did not affect the replication of these rnas ...	1997	9094656
identification of a competitive translation determinant in the 3' untranslated region of alfalfa mosaic virus coat protein mrna.	we report that the competitive translational activity of alfalfa mosaic virus coat protein mrna (cp rna), a nonadenylated mrna, is determined in part by the 3' untranslated region (utr). competitive translation was characterized both in vitro, with cotranslation assays, and in vivo, with microinjected xenopus laevis oocytes. in wheat germ extracts, coat protein synthesis was constant when a fixed amount of full-length cp rna was cotranslated with increasing concentrations of competitor globin mr ...	1997	9121448
antigens produced in plants by infection with chimeric plant viruses immunize against rabies virus and hiv-1.	the coat protein (cp) of alfalfa mosaic virus was used as a carrier molecule to express antigenic peptides from rabies virus and hiv. the antigens were separately cloned into the reading frame of alfalfa mosaic virus cp and placed under the control of the subgenomic promoter of tobacco mosaic virus cp in the 30brz vector. the in vitro transcripts of recombinant virus with sequences encoding the antigenic peptides were synthesized from dna constructs and used to inoculate tobacco plants. the plan ...	1997	9159151
turnip yellow mosaic virus rna-dependent rna polymerase: initiation of minus strand synthesis in vitro.	an rna-dependent rna polymerase (rdrp) activity was detergent-solubilized from the chloroplast membranes of chinese cabbage leaves infected with turnip yellow mosaic virus (tymv). the template-dependent, micrococcal nuclease-treated activity synthesized full-length minus strands from tymv rna and 3'-fragments as short as a 28-nucleotide-long rna comprising the amino acid acceptor stem of the 3'-trna-like structure (tls). minus strands were shown to arise by de novo initiation with the insertion ...	1997	9217066
the role of the pseudoknot at the 3' end of turnip yellow mosaic virus rna in minus-strand synthesis by the viral rna-dependent rna polymerase.	the trna-like structure at the 3' end of turnip yellow mosaic virus (tymv) rna was studied in order to determine the role of this structure in the initiation of minus-strand synthesis in vitro. deletions in the 5'-to-3' direction up to the pseudoknot structure did not result in a decrease of transcription efficiency. however, transcription efficiency was reduced twofold when a fragment of 21 nucleotides, comprising the 3'-terminal hairpin, was used as a template. trna(phe) from yeast, escherichi ...	1997	9223489
the homeobox gene gbx2, a target of the myb oncogene, mediates autocrine growth and monocyte differentiation.	the homeobox gene gbx2 was identified as a target gene of the v-myb oncoprotein encoded by the avian myeloblastosis virus (amv). gbx2 activation by c-myb requires signal transduction emanating from the cell surface while the leukemogenic amv v-myb constitutively induces the gbx2 gene. mutations in the dna binding domain of amv-myb render it independent of signaling events and concomitantly abrogate the collaboration between myb and ccaat enhancer binding proteins (c/ebp), which are involved in g ...	1997	9346236
the 3' untranslated region of alfalfa mosaic virus rna3 contains a core promoter for minus-strand rna synthesis and an enhancer element.	the 3' untranslated regions (utrs) of the three genomic rnas of alfalfa mosaic virus consist of a 3' homologous sequence of 145 nt and upstream unique sequences 18-34 nt in length. mutations were made in the 3' utr of a cdna clone of rna3. point mutations in five augc motifs which interfere with specific binding of coat protein to the 3' utr had no effect on template activity of rna3 for minus-strand rna synthesis in vitro by purified viral rna-dependent rna polymerase (rdrp). deletion analysis ...	1997	9367392
expression of the catalytic subunit (ul54) and the accessory protein (ul44) of human cytomegalovirus dna polymerase in a coupled in vitro transcription/translation system.	the catalytic subunit (ul54) and accessory protein (ul44) of human cytomegalovirus (hcmv) dna polymerase have been cloned and expressed in an in vitro-coupled transcription/translation reticulocyte lysate system. the influence of the 5'-untranslated region (5'-utr) on the efficiency of expression from the circular plasmids has been investigated. for expression of both ul54 and ul44, a truncated form of the alfalfa mosaic virus (amv) rna4 5'-utr was found to be superior to the full-length amv 5'- ...	1997	9367818
one-tube and one-buffer system of rt-pcr amplification of 1d gene of foot-and-mouth disease virus field isolates.	a method of reverse transcription (rt) and polymerase chain reaction (pcr) amplification of 1d (vp1) gene of foot-and-mouth disease (fmd) virus using one reaction mixture containing both avian myeloblastosis virus (amv) reverse transcriptase (rtase) and tfl dna polymerase is described. the procedure was time saving, made use of a single buffer for both rt and subsequent amplification and performed better than the two-step procedure usually conducted with moloney murine leukemia virus (mmlv) rtas ...	1997	9385403
occurrence of nepoviruses in rubus species in the czech republic.	the occurrence of arabis mosaic virus (amv), raspberry ringspot virus (rrv), tomato black ring virus (tbrv), strawberry latent ringspot virus (slrv) and cherry leaf roll virus (clrv) in cultivated and wild plants of raspberry and blackberry has been studied in the czech republic in 1993-1996. five hundred and seventy samples were collected at 51 localities and assayed by double antibody sandwich enzyme-linked immunosorbent assay (das-elisa). the results represent the first evidence on the occurr ...	1997	9385408
nucleoprotein complexes harboring an extrachromosomal dna closely related to 7 s dna of avian myeloblastosis virus: physico-chemical properties and representation of nucleic acids.	the source of avian myeloblastosis virus (amv) dna, an extrachromosomal small polydisperse dna, present in the material forming the postmicrosomal sediment (poms) of lysed chicken leukemic myeloblasts (chlms) is organized into nucleoprotein (np) complexes containing always rna. this material, radioactively double-labelled for dna and rna, separated in isopycnic sucrose gradients into three poms components (a,b,c) differing from one another in properties of labelling for dna and rna, sucrose dens ...	1997	9391649
activities of a lagging dna strand synthesis of nucleoprotein complexes harboring an extrachromosomal dna closely related to avian myeloblastosis virus core-bound dna.	nucleoprotein (np) complexes constituting the material of the postmicrosomal sediment (poms) and its three basic components (a, b, c) (ríman and sulová, 1997a), harboring an extrachromosomal dna closely related to amv dna were found to possess dna- and rna-synthesizing activities (sas) reflecting the ability of this material to be intensely labelled for dna and rna, respectively. the types of these na-sas were compatible with those significant for a lagging dna strand synthesis (lss). the use of ...	1997	9391650
replication of alfalfa mosaic virus rna 3 with movement and coat protein genes replaced by corresponding genes of prunus necrotic ringspot ilarvirus.	alfalfa mosaic virus (amv) and prunus necrotic ringspot virus (pnrsv) are tripartite positive-strand rna plant viruses that encode functionally similar translation products. although the two viruses are phylogenetically closely related, they infect a very different range of natural hosts. the coat protein (cp) gene, the movement protein (mp) gene or both genes in amv rna 3 were replaced by the corresponding genes of pnrsv. the chimeric viruses were tested for heterologous encapsidation, replicat ...	1997	9400967
the myb leucine zipper is essential for leukemogenicity of the v-myb protein.	the amv v-myb oncoprotein causes oncogenic transformation of myelomonocytic cells in vivo and in vitro. its transforming capacity is strictly dependent upon the n-terminal dna binding domain, the central transactivation region, and on the c-terminal domain containing a putative leucine zipper motif. here we show that the v-mybl3,4a mutant, in which leu325 and leu332 of the leucine zipper have been replaced by alanines, failed to induce leukemia in virus infected chicken. this demonstrates that t ...	1997	9416837
the 5' untranslated region of cucumber mosaic virus rna4 confers highly competitive activity on heterologous luciferase mrna in cell-free translation.	the cell-free translation of virion rnas of several tripartite rna viruses has shown that rna4, a subgenomic rna, is more competitive than other virion rnas. recently, the 3' untranslated region (utr) of alfalfa mosaic virus (amv) rna4 was identified to be a competitive determinant. in this study, we observed that the rna4 of cucumber mosaic virus (cmv), another tripartite rna virus, was also found to be a strong competitor in translational competition among cmv virion rnas. to identify the comp ...	1998	9475176
rna quantitative analysis from fixed and paraffin-embedded tissues: membrane hybridization and capillary electrophoresis.	fixed and paraffin-embedded tissues from pathology department archives are available for rna expression analysis. we describe a general method for quantitation of specific rna sequence extracted from single 6-8-micron human histological tissue sections cut from paraffin blocks. for each specific mrna, the range of linear relationship between the log of the initial total rna concentration and the log of the specific product after reverse transcription (rt)-pcr must be established. we usually perf ...	1998	9494729
bioluminometric method for real-time detection of reverse transcriptase activity.	a simple and sensitive technique for detection of reverse transcriptase (rt) activity in real time has been developed. the technique is based on continuous detection of the inorganic pyrophosphate formed in the rt-catalyzed reaction by a luminometric method. the technique has been used for continuous monitoring of rt-catalyzed dna synthesis on both homo- and heteropolymeric templates. the assay is sensitive and yields linear responses between 1.5-960 mu of avian myeloblastosis virus rt (amv-rt). ...	1998	9494733
functional significance of three basic n-terminal amino acids of alfalfa mosaic virus coat protein.	infection of tobacco protoplasts with mutant alfalfa mosaic virus (amv) rnas indicated that three basic amino acids in the n-terminus of amv coat protein are important for the biological activity of the coat protein in the beginning of infection. substitution of alanines for lysines at position 14 or 17 in the coat protein resulted in a 5- or 10-fold reduction in the activity of the protein, respectively. however, substitution of alanine for arginine at position 18 entirely abolished activity. a ...	1998	9501033
viral coat protein peptides with limited sequence homology bind similar domains of alfalfa mosaic virus and tobacco streak virus rnas.	an unusual and distinguishing feature of alfalfa mosaic virus (amv) and ilarviruses such as tobacco streak virus (tsv) is that the viral coat protein is required to activate the early stages of viral rna replication, a phenomenon known as genome activation. amv-tsv coat protein homology is limited; however, they are functionally interchangeable in activating virus replication. for example, tsv coat protein will activate amv rna replication and vice versa. although amv and tsv coat proteins have ...	1998	9525649
nitric oxide (no) disrupts specific dna binding of the transcription factor c-myb in vitro.	in an attempt to elucidate signal transduction pathways which may modulate dna binding of the transcription factor c-myb, we investigated whether c-myb could be a target for the signaling molecule nitric oxide (no) in vitro. no-generating agents severely inhibited specific dna binding of the c-myb minimal dna-binding domain r2r3. this inhibition was readily reversible upon treatment with excess dtt. a redox-sensitive cysteine (c130) was required for this no sensitivity. moreover, a dna-binding d ...	1998	9541005
regulation of single-strand rna synthesis of alfalfa mosaic virus in non-transgenic cowpea protoplasts by the viral coat protein.	we have compared the rna synthesis of alfalfa mosaic virus in complete (by rnas 1, 2 and 3) and incomplete infections (by rnas 1 and 2) of cowpea protoplasts. both viral rna polymerase activity and accumulation of viral rna were measured. by annealing rna in solution with 32p-labelled probes of plus and minus polarity followed by treatment with ribonucleases, we determined viral rnas quantitatively in both single- and double-stranded rna fractions. the accumulation of single-stranded rna of posi ...	1998	9572550
the movement protein and coat protein of alfalfa mosaic virus accumulate in structurally modified plasmodesmata.	in systemically infected tissues of nicotiana benthamiana, alfalfa mosaic virus (amv) coat protein (cp) and movement protein (mp) are detected in plasmodesmata in a layer of three to four cells at the progressing front of infection. besides the presence of these viral proteins, the plasmodesmata are structurally modified in that the desmotubule is absent and the diameter has increased drastically (almost twofold) when compared to plasmodesmata in uninfected cells or cells in which amv infection ...	1998	9601503
rna determinants of a specific rna-coat protein peptide interaction in alfalfa mosaic virus: conservation of homologous features in ilarvirus rnas.	alfalfa mosaic virus (amv) coat protein and tobacco streak virus (tsv) coat protein bind specifically to the 3' untranslated regions of the viral rnas and are required with the genomic rnas to initiate virus replication. a combination of nucleotide substitutions, hydroxyl radical footprinting, and ethylation and chemical modification interference analysis has been used to define the rna determinants important for the specific binding of the 3'-terminal 39 nucleotides of amv rna 3/4 (amv843-881) ...	1998	9614941
cell-to-cell movement of beet necrotic yellow vein virus: i. heterologous complementation experiments provide evidence for specific interactions among the triple gene block proteins.	cell-to-cell movement of beet necrotic yellow vein virus (bnyvv) requires three proteins encoded by a triple gene block (tgb) on viral rna 2. a bnyvv rna 3-derived replicon was used to express movement proteins to functionally substitute for the bnyvv tgb proteins was tested by coinoculation of tgb-defective bnyvv with the various replicons to chenopodium quinoa. trans-heterocomplementation was successful with the movement protein (p30) of tobacco mosaic virus but not with the tubule-forming mov ...	1998	9650295
the sequence of rna 1 and rna 2 of tobacco streak virus: additional evidence for the inclusion of alfalfa mosaic virus in the genus ilarvirus.	here we describe the complete sequence of rna 1 and 2 of the wc isolate of tobacco streak virus (tsv). these two sequences complete the information on the genome of tsv, the type member of the genus ilarvirus, and are the first sequences described for the rna 1 and rna 2 of a member of subgroup 1 of this genus. the sequences have a similar organization to those reported for the corresponding rnas of other ilarviruses. however, the putative translation products of these two molecules differ suffi ...	1998	9687875
comparison of three rna amplification methods as sources of dna for sequencing.	dna products generated from a region of the measles virus genome by three rna reverse transcription and amplification methods were cloned and sequenced, and the results were compared in order to evaluate the methods' relative fidelities. the methods were: (i) reverse transcription followed by a nested polymerase chain reaction (rt-npcr), (ii) a combined rt-pcr using rtth polymerase and (iii) nucleic acid sequence-based amplification (nasba). nasba was followed by rt-pcr with rtth polymerase or r ...	1998	9821583
amino acids of alfalfa mosaic virus coat protein that direct formation of unusually long virus particles.	in contrast to most alfalfa mosaic virus (amv) strains (ysmv, s, m and 425), amv strains vru and 1 5/64 can form abnormally long virus particles, an ability which has been linked to the coat protein (cp). in order to study this phenomenon, the cp-encoding rnas 3 of amv strains vru and 1 5/64 were cloned and fully sequenced. comparative sequence analyses of amv rna 3 sequences derived from different strains revealed two non-conservative amino acid substitutions, ser65 and leu175, which occur excl ...	1998	9880033
a core promoter hairpin is essential for subgenomic rna synthesis in alfalfa mosaic alfamovirus and is conserved in other bromoviridae.	the nucleotide sequence immediately in front of the initiation site for subgenomic rna 4 synthesis on rna 3 minus strand, which has been proved to function as a core promoter, was inspected for secondary structure in 26 species of the plant virus family bromoviridae. in 23 cases a stable hairpin could be predicted at a distance of 3 to 8 nucleotides from the initiation site of rna 4. this hairpin contained several conserved nucleotides that are essential for core promoter activity in brome mosai ...	1998	9926399
dna synthesis exhibited by the reverse transcriptase of mouse mammary tumor virus: processivity and fidelity of misinsertion and mispair extension.	we have recently expressed in bacteria an enzymatically active reverse transcriptase (rt) of mouse mammary tumor virus (mmtv), a mammalian retrovirus with a typical b-type morphology [taube, r., loya, s., avidan, o., perach, m. & hizi, a. (1998) biochemical j. 329, 579-587]. the purified recombinant protein was shown to possess the catalytic activities characteristic of retroviral reverse transcriptases. in the present study, we have analyzed two basic parameters characteristic of the dna polyme ...	1998	9990322
scope for using plant viruses to present epitopes from animal pathogens.	epitope presentation to the immune system for vaccination purposes can be achieved either via an inactivated or attenuated form of a pathogen or via its isolated antigenic sequences. when free, these peptides can adopt a variety of conformations, most of which will not exist in their native environment. conjugation to carrier proteins restricts mobility of the peptides and increases their immunogenicity. a high local concentration of epitopes boosts the immune response further and can be generat ...	1998	10398492
effect of c-terminal mutations of alfalfa mosaic virus coat protein on dimer formation and assembly in vitro.	the coat protein (cp) of alfalfa mosaic virus (amv) strain 425 assembles to bacilliform or rod-shaped particles in the presence of nucleic acids or to t = 1 empty icosahedral particles in the absence of nucleic acids. to study the determinants of cp assembly, recombinant cps (rcps) that contained a (his)(6) region were expressed in escherichia coli. wt rcp and a mutant rcp, which lacked the last nine amino acids of the c terminus (amino acids 213-221), assembled to particles that were identical ...	1999	10405370
genome activation in alfamo- and ilarviruses.	alfamo- and ilarviruses are characterized by the deficiency of their genomes (three messenger-sense rnas) to start an infection cycle. the rnas are in capsids built from a single species of protein of about 24 kd. a few dimers of this coat protein per rna molecule are sufficient to activate the genome. since the first description of genome activation [bol jf, van vloten-doting l, jaspars emj (1971) virology 46: 73-85] three models have been proposed concerning its mechanism: the protection, the ...	1999	10416370
a conformational switch at the 3' end of a plant virus rna regulates viral replication.	3' untranslated regions of alfamo- and ilar-virus rnas fold into a series of stem-loop structures to which the coat protein binds with high affinity. this binding plays a role in initiation of infection ('genome activation') and has been thought to substitute for a trna-like structure that is found at the 3' termini of related plant viruses. we propose the existence of an alternative conformation of the 3' ends of alfamo- and ilar-virus rnas, including a pseudoknot. based on (i) phylogenetic com ...	1999	10469663
expression of alfalfa mosaic virus coat protein in tobacco mosaic virus (tmv) deficient in the production of its native coat protein supports long-distance movement of a chimeric tmv.	alfalfa mosaic virus (almv) coat protein is involved in systemic infection of host plants, and a specific mutation in this gene prevents the virus from moving into the upper uninoculated leaves. the coat protein also is required for different viral functions during early and late infection. to study the role of the coat protein in long-distance movement of almv independent of other vital functions during virus infection, we cloned the gene encoding the coat protein of almv into a tobacco mosaic ...	1999	10051680
alfalfa mosaic virus rnas serve as cap donors for tomato spotted wilt virus transcription during coinfection of nicotiana benthamiana.	tomato spotted wilt virus (tswv) was shown to use alfalfa mosaic virus (amv) rnas as cap donors in vivo during a mixed infection in nicotiana benthamiana. by use of nested reverse transcription-pcr, tswv n and nss mrnas provided with capped leader sequences derived from all four amv rnas could be cloned and sequenced. the sequence specificity of the putative tswv endonuclease involved is discussed.	1999	10233983
alfalfa mosaic virus and ilarviruses: involvement of coat protein in multiple steps of the replication cycle.		1999	10355754
transformation by v-myb.	the v-myb oncogene of the avian myeloblastosis virus (amv) is unique among known oncogenes in that it causes only acute leukemia in animals and transforms only hematopoietic cells in culture. amv was discovered in the 1930s as a virus that caused a disease in chickens that is similar to acute myelogenous leukemia in humans (hall et al., 1941). this avian retrovirus played an important role in the history of cancer research for two reasons. first, amv was used to demonstrate that all oncogenic vi ...	1999	10378700
cis-acting functions of alfalfa mosaic virus proteins involved in replication and encapsidation of viral rna.	cdna clones of rnas 1 and 2 of alfalfa mosaic virus (amv) were slightly modified to permit transcription of infectious rnas with t7 rna polymerase. together with transcripts of an available clone of amv rna 3, these transcripts were used to study cis- and trans-acting functions of amv proteins in protoplasts from nontransgenic tobacco plants and from plants transformed with the p1 and p2 genes, encoded by rnas 1 and 2, respectively. transgenic p1 was unable to complement mutations in the p1 gene ...	1999	9986798
high temperature cdna synthesis by amv reverse transcriptase improves the specificity of pcr.	the enzyme avian myeloblastosis virus reverse transcriptase (amv-rt) is routinely used for cdna synthesis, which is generally carried out at temperatures between 37 degrees c and 42 degrees c. we show that this enzyme can support cdna synthesis, at temperatures as high as 70 degrees c. we have utilized this property of the amv-rt to improve the specificity of polymerase chain reaction (pcr). furthermore, this apparently thermophilic property of the enzyme, which is an important constituent of a ...	1999	10631680
the "small" polydisperse cytoplasmic extrachromosomal dna of chicken leukaemic myeloblasts and the avian myeloblastosis virus core-bound dna seem to descend from origin regions of chromosomal dna replication.	nucleotide sequences are presented for 12, 7 and 12 cloned extrachromosomal dnas by nature harbored in nucleoprotein (np) complexes forming chicken leukaemic myeloblast (chlm) post microsomal sediment (poms) components a, b and c, respectively, and for 11 cloned avian myeloblastosis virus (amv) dnas. analysis of the abundance of sequence motifs significant for eukaryotic chromosomal dna replication origin (ori) regions (and their initiation zones) has shown that these dnas are reminiscent of cel ...	1999	10672338
genetic dissection of the multiple functions of alfalfa mosaic virus coat protein in viral rna replication, encapsidation, and movement.	coat protein (cp) of alfalfa mosaic virus (amv) binds as a dimer to the 3' termini of the three genomic rnas and is required for initiation of infection, asymmetric plus-strand rna accumulation, virion formation, and spread of the virus in plants. a mutational analysis of the multiple functions of amv cp was made. mutations that interfered with cp dimer formation in the two-hybrid system had little effect on the initiation of infection or plus-strand rna accumulation but interfered with virion f ...	2000	10683324
detection and sequencing of measles virus from peripheral mononuclear cells from patients with inflammatory bowel disease and autism.	it has been reported that measles virus may be present in the intestine of patients with crohn's disease. additionally, a new syndrome has been reported in children with autism who exhibited developmental regression and gastrointestinal symptoms (autistic enterocolitis), in some cases soon after mmr vaccine. it is not known whether the virus, if confirmed to be present in these patients, derives from either wild strains or vaccine strains. in order to characterize the strains that may be present ...	2000	10759242
determining 'threshold' levels for seed-borne virus infection in seed stocks.	there have been many advances in testing procedures to detect seed-borne virus infection in seed samples. however, scant attention has been given to the implications of improved test results in terms of the economic losses resulting from sowing seed stocks with different amounts of infection. for agricultural and horticultural industries to use the results of tests on representative samples, defined 'threshold' values for percentage seed infection are required that identify acceptable levels of ...	2000	11137171
the complete nucleotide sequence of apple mosaic virus (apmv) rna 1 and rna 2: apmv is more closely related to alfalfa mosaic virus than to other ilarviruses.	the complete nucleotide sequences of apple mosaic virus rna 1 and 2 have been characterized. apple mosaic virus rna 1 is 3476 nucleotides in length and encodes a single large open reading frame (orf), whereas apple mosaic virus rna 2 is 2979 nucleotides in length and also encodes a single orf. the amino acid sequences encoded by rna 1 and 2 show similarity to all of the other ilarviruses for which sequence data are available, but both are more closely related to alfalfa mosaic virus (amv) than t ...	2000	10640567
activation of the alfalfa mosaic virus genome by viral coat protein in non-transgenic plants and protoplasts. the protection model biochemically tested.	in non-transgenic host plants and protoplasts alfalfa mosaic virus displays a strong need for coat protein when starting an infection cycle. the "protection model" states that the three viral rnas must have a few coat protein subunits at their 3' termini in order to protect them in the host cell against degradation by 3'- to- 5' exoribonucleases [neeleman l, van der vossen eag, bol jf (1993) virology 196: 883-887]. we demonstrated that the naked genome rnas are slightly infectious, if the inocul ...	2000	10664403
a conserved hairpin structure in alfamovirus and bromovirus subgenomic promoters is required for efficient rna synthesis in vitro.	the coat protein gene in rna 3 of alfalfa mosaic virus (amv; genus alfamovirus, family bromoviridae) is translated from the subgenomic rna 4. analysis of the subgenomic promoter (sgp) in minus-strand rna 3 showed that a sequence of 37 nt upstream of the rna 4 start site (nt +1) was sufficient for full sgp activity in an in vitro assay with the purified viral rna-dependent rna-polymerase (rdrp). the sequence of nt -6 to -29 could be folded into a potential hairpin structure with a loop represente ...	2000	10836792
cowpea mosaic virus infection induces a massive proliferation of endoplasmic reticulum but not golgi membranes and is dependent on de novo membrane synthesis.	replication of cowpea mosaic virus (cpmv) is associated with small membranous vesicles that are induced upon infection. the effect of cpmv replication on the morphology and distribution of the endomembrane system in living plant cells was studied by expressing green fluorescent protein (gfp) targeted to the endoplasmic reticulum (er) and the golgi membranes. cpmv infection was found to induce an extensive proliferation of the er, whereas the distribution and morphology of the golgi stacks remain ...	2000	10864669
avian retrovirus dna internal attachment site requirements for full-site integration in vitro.	concerted integration of retrovirus dna termini into the host chromosome in vivo requires specific interactions between the cis-acting attachment (att) sites at the viral termini and the viral integrase (in) in trans. in this study, reconstruction experiments with purified avian myeloblastosis virus (amv) in and retrovirus-like donor substrates containing wild-type and mutant termini were performed to map the internal att dna sequence requirements for concerted integration, here termed full-site ...	2000	10954527
human respiratory syncytial virus vaccine antigen produced in plants.	human respiratory syncytial virus (rsv) is the primary cause of respiratory infection in infants worldwide. currently there is no available vaccine, although studies in animal models have demonstrated protective immunity induced by an epitope of the rsv g-protein representing amino acids 174-187. two peptides containing amino acids 174-187 of the g-protein of the human rsv a2 strain (nf1-rsv/172-187 and nf2-rsv/170-191) were separately engineered as translational fusions with the alfalfa mosaic ...	2000	11053254
tax oncoprotein trans-represses endogenous b-myb promoter activity in human t cells.	the b-myb gene was identified on the basis of its homology with the protooncogene c-myb, homolog of the avian myeloblastosis virus (amv) and avian leukemia virus (e26) transforming genes. several studies using antisense constructs or antisense oligonucleotides as well as overexpression experiments suggest that b-myb plays an important role in the transition from g(1) to s phase of the cell cycle and that b-myb expression is cell cycle regulated. we have previously demonstrated that the human t c ...	2000	11080802
evidence for two distinct subgroups of alfalfa mosaic virus (amv) from france and italy and their relationships with other amv strains brief report.	the nucleotide sequence of the putative coat protein open reading frame of seven previously uncharacterized amv strains from italy and france was determined and aligned with comparable sequences of other amv strains (425 l, 425 m, ysmv, s, vru, 15/64 and da). the data set of amv sequences was used to determine phylogenetic relationships by both a stochastic (stationary markov model) and a deterministic method (maximum-parsimony) of analysis. the topology of the trees obtained with the two method ...	2000	11205111
in vitro transcription by the turnip yellow mosaic virus rna polymerase: a comparison with the alfalfa mosaic virus and brome mosaic virus replicases.	recently, we showed that the main determinant in the trna-like structure of turnip yellow mosaic virus rna to initiate minus-strand synthesis in vitro is the 3' acca end. by mutational analysis of the 3'-terminal hairpin, we show here that only a non-base-paired acca end is functional and that the stability of the wild-type 3'-proximal hairpin is the most favorable, in that it has the lowest deltag value and a high transcription efficiency. with a nested set of rna fragments, we show that the mi ...	2000	10590114
varied molecular interactions at the active sites of several dna polymerases: nonpolar nucleoside isosteres as probes.	we describe a survey of protein-dna interactions with seven different dna polymerases and reverse transcriptases, carried out with nonpolar nucleoside isosteres f (a thymidine analog) and z and q (deoxyadenosine analogues). previous results have shown that z and f can be efficiently replicated opposite each other by the exonuclease-free klenow fragment of dna polymerase i from escherichia coli (kf(-)), although both of them lack watson-crick h-bonding ability. we find that exonuclease-inactive t ...	2000	20882113
pathogenesis of alfalfa mosaic virus in soybean (glycine max) and expression of chimeric rabies peptide in virus-infected soybean plants.	abstract infection of soybean (glycine max) plants inoculated with particles of alfalfa mosaic virus (almv) isolate 425 at 12 days after germination was monitored throughout the life cycle of the plant (vegetative growth, flowering, seed formation, and seed maturation) by western blot analysis of tissue samples. at 8 to 10 days after inoculation, the upper uninoculated leaves showed symptoms of virus infection and accumulation of viral coat protein (cp). virus cp was detectable in leaves, stem, ...	2001	18944120
recognition of cis-acting sequences in rna 3 of prunus necrotic ringspot virus by the replicase of alfalfa mosaic virus.	alfalfa mosaic virus (amv) and prunus necrotic ringspot virus (pnrsv) belong to the genera alfamovirus: and ilarvirus:, respectively, of the family bromoviridae: initiation of infection by amv and pnrsv requires binding of a few molecules of coat protein (cp) to the 3' termini of the inoculum rnas and the cps of the two viruses are interchangeable in this early step of the replication cycle. cis:-acting sequences in pnrsv rna 3 that are recognized by the amv replicase were studied in in vitro re ...	2001	11257202
the chicken pdcd4 gene is regulated by v-myb.	the retroviral oncogene v-myb encodes a transcription factor (v-myb) which is responsible for the ability of avian myeloblastosis virus (amv) to transform myelomonocytic cells. v-myb is thought to disrupt the differentiation of myelomonocytic cells by affecting the expression of specific target genes. to identify such genes we have analysed the gene expression in a myelomonocytic chicken cell line that carries an estrogen inducible version of v-myb by differential display. here we describe the i ...	2001	11313950
natural minus-strand rnas of alfalfa mosaic virus as in vitro templates for viral rna polymerase. 3'-terminal non-coded guanosine and coat protein are insufficient factors for full-size plus-strand synthesis.	replication complexes of alfalfa mosaic virus produce in vivo large quantities of plus-strand rnas, but this production is fully dependent on the presence of coat protein. in order to study this process of rna-dependent and coat protein-regulated rna synthesis we have isolated the three natural minus-strand rnas (containing any posttranscriptional modification that might have occurred) and have tested them for coat protein binding sites and template activity in an in vitro system with the viral ...	2001	11338391
in vivo analysis of the tswv cap-snatching mechanism: single base complementarity and primer length requirements.	requirements for capped leader sequences for use during transcription initiation by tomato spotted wilt virus (tswv) were tested using mutant alfalfa mosaic virus (amv) rnas as specific cap donors in transgenic nicotiana tabacum plants expressing the amv replicase proteins. using a series of amv rna3 mutants modified in either the 5'-non-translated region or in the subgenomic rna4 leader, sequence analysis revealed that cleaved leader lengths could vary between 13 and 18 nucleotides. cleavage oc ...	2001	11350944
an example of application of molecular techniques to the study on the local regulatory system controlling the function of the rat male gonad.	molecular biology techniques help to study details of testicular cell interactions, which play an important role in the control of spermatogenesis and secretory function of the male gonad. this paper presents an example of application of such techniques, with evaluation of their usability, in the study on expression of some cytokines involved in cellular interactions in the rat testis. testicular cells were isolated by digestion with collagenase followed by percoll gradient centrifugation or by ...	2001	11374783
role of the 3'-untranslated regions of alfalfa mosaic virus rnas in the formation of a transiently expressed replicase in plants and in the assembly of virions.	alfalfa mosaic virus (amv) rnas 1 and 2 encode the replicase proteins p1 and p2, respectively, whereas rna 3 encodes the movement protein and the coat protein (cp). when rnas 1 and 2 were transiently expressed from a t-dna vector (r12 construct) by agroinfiltration of nicotiana benthamiana, the infiltrated leaves accumulated minus-strand rnas 1 and 2 and relatively small amounts of plus-strand rnas. in addition, rna-dependent rna polymerase (rdrp) activity could be detected in extracts of the in ...	2001	11413311
engineering of alfalfa mosaic virus rna 3 into an expression vector.	rna 3 of alfalfa mosaic virus (amv) encodes the 5'-proximal movement protein (mp) gene and the 3'-proximal coat protein (cp) gene which is expressed from a subgenomic rna. several strategies were explored to use this rna as a vector for expression of the green fluorescent protein (gfp) in nicotiana tabaccum plants expressing the viral polymerase proteins p1 and p2 (p12 plants). insertion of a subgenomic promoter (sgp)-gfp cassette between the cp gene and the 3'-untranslated region (utr) interfer ...	2001	11448030
role of the alfalfa mosaic virus movement protein and coat protein in virus transport.	the movement protein (mp) and coat protein (cp) encoded by alfalfa mosaic virus (amv) rna 3 are both required for virus transport. rna 3 vectors that expressed nonfused green fluorescent protein (gfp), mp:gpf fusions, or gfp:cp fusions were used to study the functioning of mutant mp and cp in protoplasts and plants. c-terminal deletions of up to 21 amino acids did not interfere with the function of the cp in cell-to-cell movement, although some of these mutations interfered with virion assembly. ...	2001	11551070
intracellular localization and movement phenotypes of alfalfa mosaic virus movement protein mutants.	thirteen mutations were introduced in the movement protein (mp) gene of alfalfa mosaic virus (amv) fused to the green fluorescent protein (gfp) gene and the mutant mp-gfp fusions were expressed transiently in tobacco protoplasts, tobacco suspension cells, and epidermal cells of tobacco leaves. in addition, the mutations were introduced in the mp gene of amv rna 3 and the mutant rnas were used to infect tobacco plants. ten mutants were affected in one or more of the following functions of mp: the ...	2001	11551071
rnas 1 and 2 of alfalfa mosaic virus, expressed in transgenic plants, start to replicate only after infection of the plants with rna 3.	rnas 1 and 2 of the tripartite genome of alfalfa mosaic virus (amv) encode the two viral replicase subunits. full-length dna copies of rnas 1 and 2 were used to transform tobacco plants (r12 lines). none of the transgenic lines showed resistance to amv infection. in healthy r12 plants, the transcripts of the viral cdnas were copied by the transgenic viral replicase into minus-strand rnas but subsequent steps in replication were blocked. when the r12 plants were inoculated with amv rna 3, this bl ...	2001	11125154
alfalfa mosaic virus replicase proteins p1 and p2 interact and colocalize at the vacuolar membrane.	replication of alfalfa mosaic virus (amv) rnas depends on the virus-encoded proteins p1 and p2. p1 contains methyltransferase- and helicase-like domains, and p2 contains a polymerase-like domain. coimmunoprecipitation experiments revealed an interaction between in vitro translated-p1 and p2 and showed that these proteins are present together in fractions with rna-dependent rna polymerase activity. a deletion analysis in the yeast two-hybrid system showed that in p1 the c-terminal sequence of 509 ...	2001	11160687
crystals of ternary protein-dna complexes composed of dna-binding domains of c-myb or v-myb, c/ebpalpha or c/ebpbeta and tom-1a promoter fragment.	c-myb and the c/ebp family are transcriptional regulatory factors that act in concert to regulate the expression of myeloid-specific genes. v-myb encoded by avian myeloblastosis virus (amv) is a mutated form of c-myb that contains point mutations which disrupt the cooperation with c/ebps. to understand the mechanism of the transcriptional synergy between c-myb and c/ebps and the effect of the v-myb mutations on that synergy, knowledge based on their three-dimensional structures is essential. cry ...	2001	11679735
[analysis of the viral capsid gene of alfalfa mosaic virus (cp a1mv) cloned to the vector for plant transformation pbi121].	the virus gene cp almv cloned to the vector pbi121 (clontech) was analyzed using the method of restriction analysis and polymerase chain reaction. the restriction analysis with the use of apai enzyme has shown presence of the specific fragment with a part of cp gene about 2.5 kb. the same procedure with ecori and hindiii enzymes has shown difference in electrophoretic migration of the formed fragments. polymerase chain reaction analysis has shown the existence of the specific amplification produ ...	2001	11692679
translation of a nonpolyadenylated viral rna is enhanced by binding of viral coat protein or polyadenylation of the rna.	on entering a host cell, positive-strand rna virus genomes have to serve as messenger for the translation of viral proteins. efficient translation of cellular messengers requires interactions between initiation factors bound to the 5'-cap structure and the poly(a) binding protein bound to the 3'-poly(a) tail. initiation of infection with the tripartite rna genomes of alfalfa mosaic virus (amv) and viruses from the genus ilarvirus requires binding of a few molecules of coat protein (cp) to the 3' ...	2001	11717411
anatomy of the primase-alpha dna polymerase reaction accomplished by nucleoprotein complexes harboring an extrachromosomal dna identical with avian myeloblastosis virus core-bound dna: influencing by carbonyldiphosphonate, mimosine and butylphenyl deoxyguanosine-5'-triphosphate.	activities of the primase (pr)-alpha dna polymerase (pol) enzyme complex belonging to the naturally occurring reaction systems represented by special np complexes harboring an extrachromosomal dna identical with avian myeloblastosis virus (amv) core-bound dna (j. riman, a. sulová and k. horská, acta virol. 39, 149-159 (1995); j. ríman and a. sulová, acta virol. 41, 181-192 (1997)) were studied in the absence and presence of carbonyldiphosphonate (comdp), mimosine (mimo), to it related ciclopirox ...	2001	11719981
detection of human immunodeficiency virus type 1 reverse transcriptase using aptamers as probes in affinity capillary electrophoresis.	an affinity capillary electrophoresis/laser-induced fluorescence (ce/lif) assay was developed for direct and specific detection of reverse transcriptase (ri) of the type 1 human immunodeficiency virus (hiv-1) using fluorescently labeled single-stranded dna aptamers as probes. the aptamer used (rt 26) is specific for hiv-1 rt, and it exhibited no cross-reactivity with rts of the enhanced avian myeloblastosis virus (amv), the moloney murine leukemia virus (mmlv), or denatured hiv-1 rt. an affinity ...	2001	11791582
new host-virus relations between different solanum species and viruses.	we have studied the susceptibility or resistance of solanum capsicastrum link. et schauer, s. comatum sendt., s. dulcamara l., s. luteum mill., s. malacoxylon sendt. and s. nigrum l. to three aphid transmissible viruses [alfalfa mosaic alfamovirus (amv), potato m. carlavirus (pvm) and potato s carlavirus (pvs)]. out of the species, s. capsicastrum, s. comatum, s. dulcamara, s. malacoxylon and s. nigrum to amv, s. capsicastrum and s. malacoxylon to pvm and s. capsicastrum, s. luteum and s. nigrum ...	2001	12425036
purified tomato spotted wilt virus particles support both genome replication and transcription in vitro.	purified tomato spotted wilt virus particles were shown to support either genome replication or transcription in vitro, depending on the conditions chosen. transcriptional activity was observed only upon addition of rabbit reticulocyte lysate, indicating a dependence on translation. under these conditions rna molecules of subgenomic length were synthesized that hybridized to strand-specific probes for the n and nss genes. cloning of these transcripts demonstrated the presence of nonviral leader ...	2002	12490389
[old and new prescriptions for infectious diseases and the newest recipes for biomedical products in plants].	the three antiviral vaccines discovered in the 18th century (smallpox), 19th century (rabies), and 20th century (polio) share a common feature: none would ever be licensed today for human vaccination. yet jenner's smallpox vaccine led to the eradication of smallpox, pasteur's rabies vaccine represented the first successful post-exposure treatment of people bitten by rabid animals, and polio vaccine administered since its discovery in 1950 is leading to the eradication of polio (in the years 2004 ...	2002	12549429
mechanism of c-myb-c/ebp beta cooperation from separated sites on a promoter.	c-myb, but not avian myeloblastosis virus (amv) v-myb, cooperates with c/ebp beta to regulate transcription of myeloid-specific genes. to assess the structural basis for that difference, we determined the crystal structures of complexes comprised of the c-myb or amv v-myb dna-binding domain (dbd), the c/ebp beta dbd, and a promoter dna fragment. within the c-myb complex, a dna-bound c/ebp beta interacts with r2 of c-myb bound to a different dna fragment; point mutations in v-myb r2 eliminate suc ...	2002	11792321
a genome-activating n-terminal coat protein peptide of alfalfa mosaic virus is able to activate infection by rnas 1, 2 and 3 but not by rnas 1 and 2. further support for the messenger release hypothesis.	an n-terminal genome-activating peptide of 25 amino acid residues of alfalfa mosaic virus coat protein was unable to activate the incomplete viral genome consisting of rnas 1 and 2. the messenger release hypothesis predicts that rna 3 must complement such an inoculum in order to produce rna 4 that will trigger the process. this is shown indeed to be the case.	2002	12038695
high processivity of the reverse transcriptase from a non-long terminal repeat retrotransposon.	r2 is a retrotransposable element that specifically inserts into the 28 s rrna genes of arthropods. the element encodes a single protein with endonuclease activity that cleaves the 28 s gene target site and reverse transcriptase (rt) activity that uses the cleaved dna to prime reverse transcription. here we compare various properties of the r2 rt activity with those of the well characterized retroviral rt, avian myeloblastosis virus (amv). in processivity assays using heterogeneous rna templates ...	2002	12101182
the role of template-primer in protection of reverse transcriptase from thermal inactivation.	we compared the thermal stabilities of wild-type recombinant avian myeloblastosis virus (amv) and moloney murine leukemia virus (m-mlv) reverse transcriptase (rt) with those of mutants of the recombinant enzymes lacking rnase h activity. they differed in resistance to thermal inactivation at elevated temperatures in the presence of an rna/dna template-primer. rnase h-minus rts retained the ability to efficiently synthesize cdna at much higher temperatures. we show that the structure of the templ ...	2002	12136094
expression in plants and immunogenicity of plant virus-based experimental rabies vaccine.	a new approach to the production and delivery of vaccine antigens is the use of engineered amino virus-based vectors. a chimeric peptide containing antigenic determinants from rabies virus glycoprotein (g protein) (amino acids 253-275) and nucleoprotein (n protein) (amino acids 404-418) was pcr-amplified and cloned as a translational fusion product with the alfalfa mosaic virus (almv) coat protein (cp). this recombinant cp was expressed in two plant virus-based expression systems. the first one ...	2002	12163267
role of an essential triloop hairpin and flanking structures in the 3' untranslated region of alfalfa mosaic virus rna in in vitro transcription.	the minus-strand promoter of alfalfa mosaic virus (amv), a tripartite plant virus belonging to the family bromoviridae, is located within the 3'-terminal 145 nucleotides (nt), which can adopt a trna-like structure (tls). this contrasts with the subgenomic promoter for rna4 synthesis, which requires approximately 40 nt and forms a single triloop hairpin. detailed analysis of the minus-strand promoter now shows that a similar triloop hairpin, hairpin e (hpe), is crucial for minus-strand synthesis. ...	2002	12163595
the deoxyribo-mode expression of primase activities of the primase-alpha dna polymerase enzyme complex associated with nucleoprotein complexes harboring an extrachromosomal dna identical with avian myeloblastosis virus core-bound dna: influencing by carbonyldiphosphonate, mimosine and butylphenyl deoxyguanosine-5'-triphosphate.	the deoxyribo-mode expression of primase (pr) activities of the pr-alpha dna polymerase (pol) enzyme complex belonging to the naturally occurring nucleoprotein (np) complexes harboring an extrachromosomal dna identical with avian myeloblastosis virus (amv) core-bound dna (ríman and sulová, acta virol. 41, 181-192 (1997)) is similarly influenced by carbonyldiphosphonate (comdp) as the ribo-mode expression of pr activities (ríman, acta virol. 45, 109-124 (2001)). in the presence of all four common ...	2002	12387498
role of the alfalfa mosaic virus methyltransferase-like domain in negative-strand rna synthesis.	rnas 1 and 2 of the tripartite genome of alfalfa mosaic virus (amv) encode the replicase proteins p1 and p2, respectively. p1 contains a methyltransferase-like domain in its n-terminal half, which has a putative role in capping the viral rnas. six residues in this domain that are highly conserved in the methyltransferase domains of alphavirus-like viruses were mutated individually in amv p1. none of the mutants was infectious to plants. mutant rna 1 was coexpressed with wild-type (wt) rnas 2 and ...	2002	12388692
pathogenesis of alfalfa mosaic virus in soybean (glycine max) and expression of chimeric rabies peptide in virus-infected soybean plants-a reexamination.		2002	18943878