Publications

the effects of paromomycin on the fidelity of translation in a yeast cell-free system.	the effects of the aminoglycoside antibiotic paromomycin on the fidelity of translation of the synthetic template poly(u), and two natural mrnas (rabbit globin mrna and brome mosaic virus rna), were examined in an mrna-dependent cell-free system from the yeast saccharomyces cerevisiae. at antibiotic concentrations that did not inhibit translation (100 microm) optimal mistranslation of all three templates was observed, with the effects declining at higher antibiotic concentrations. synthesis of t ...	1984	6388640
mutant viral rnas synthesized in vitro show altered aminoacylation and replicase template activities.	a remarkable feature of the genomic rnas of several plant viruses is the presence at the 3' end of a region that exhibits trna-like functions, including aminoacylation. the three genomic and single subgenomic rnas of brome mosaic virus (bmv) accept tyrosine in vitro and in vivo, the smallest 3' fragment that can be aminoacylated being about 135 nucleotides long. the roles of the trna-like properties are incompletely understood, but an involvement in replication rather than translational function ...	1984	6472477
nucleotide sequence of cucumber-mosaic-virus rna 2 reveals a translation product significantly homologous to corresponding proteins of other viruses.	the nucleotide sequence of the 3035 residues of rna 2 (mr 1.03 x 10(6) ) of the q strain of cucumber mosaic virus (cmv) was determined by sequencing m13 clones of the rna 2 cdna and by dideoxy sequencing using primers prepared either from m13 clones or by chemical synthesis. a single long open reading frame starts at the second aug from the 5' end of rna 2 and encodes 839 amino acids (mr 94333). this frame has flanking regions of 92 nucleotides at the 5' terminus and 423 nucleotides at the 3' te ...	1984	6547906
cdna cloning and in vitro transcription of the complete brome mosaic virus genome.	complete cdna copies of each of the brome mosaic virus genomic rnas (3.2, 2.8, and 2.1 kilobases in length) were cloned in a novel transcription vector, ppm1, designed to provide exact control of the transcription initiation site. after cleavage at a unique ecori site immediately downstream of the inserted cdna, these clones can be transcribed in vitro by escherichia coli rna polymerase to yield complete copies of the brome mosaic virus rnas. dideoxy sequencing of 5' transcript cdna runoff produ ...	1984	6549346
rna-dependent rna polymerase isolated from cowpea chlorotic mottle virus-infected cowpeas is specific for bromoviral rna.	an rna-dependent rna polymerase activity capable of synthesizing full length double-stranded rna products only in the presence of bromoviral rna templates has been isolated from cowpea chlorotic mottle virus (ccmv)-infected cowpeas. no comparable discrete products were obtained when a nonbromoviral (cowpea mosaic virus) rna was used as template. heterodisperse, ribonuclease-sensitive products were obtained in reactions catalyzed by similar extracts from mock-inoculated (uninfected) plants in the ...	1984	18639798
multicomponent rna plant virus infection derived from cloned viral cdna.	in vitro transcripts from mixtures of appropriate brome mosaic virus (bmv) cdna clones are infectious when inoculated onto barley plants. infectivity depends on in vitro transcription and on the presence of transcripts from clones of all three bmv genetic components. infectivity is destroyed by rnase after transcription, but it is insensitive to rnase before or to dnase after transcription. virion rnas from plants infected with cdna transcripts hybridize to bmv-specific probes and coelectrophore ...	1984	16593527
the three-dimensional folding of the trna-like structure of tobacco mosaic virus rna. a new building principle applied twice.	the structure of the trna-like 3' terminus of tobacco mosaic virus (tmv) rna has been studied. a 3' -terminal fragment possessing the trna-like properties was probed with chemical modification and enzymatic digestions. a model of the secondary structure is proposed for the last 105 nucleotides. the corresponding region of other tobamoviral rnas can be folded in an identical secondary structure. a three-dimensional model for the trna-like structure is given which is compared with those proposed e ...	1984	16453568
localization of the replicase recognition site within brome mosaic virus rna by hybrid-arrested rna synthesis.	3' terminal fragments of bmv rna as short as 153 bases in length serve as efficient templates in vitro for bmv-specific rna polymerase. template activity of such fragments or of native bmv rna is abolished when cdna fragments as short as 39 bases are hybridized to their 3' termini. hybridization of cdna fragments to regions of bmv rna 200 or more bases distal to the 3' end has no discernible effect on initiation and little effect on elongation. we conclude that bmv rna polymerase initiates bindi ...	1984	24310258
homology between the proteins encoded by tobacco mosaic virus and two tricornaviruses.	a comparison was made of the amino acid sequences of the proteins encoded by rnas 1 and 2 of alfalfa mosaic virus (a1mv) and brome mosaic virus (bmv), and the 126k and 183k proteins encoded by tobacco mosaic virus (tmv). three blocks of extensive homology of about 200 to 350 amino acids each were observed. two of these blocks are located in the a1mv and bmv rna 1 encoded proteins and the tmv encoded 126k protein; they are situated at the n-terminus and c-terminus, respectively. the third block i ...	1984	24310571
interaction of spermidine with viral rna and its influence on protein synthesis.	addition of spermidine to a cell-free protein synthesizing system from wheat germ programmed with total brome mosaic virus (bmv) rna resulted in a several-fold stimulation of amino acid incorporation. increasing the spermidine concentration in the system led to inhibition of the overall protein synthesis, but the production of longer polypeptides was inhibited much more than that of the coat protein (shorter product). analysis of the products synthesized under direction of bmv rna 3 (longer prod ...	1985	24310653
specificity of rna and coat protein interaction in alfalfa mosaic virus and related viruses.	well-defined coat protein binding sites were found to be present on the genomic rnas of almv and tsv. in view of the regulatory importance of these sites in virus multiplication, the possibility that nonrelated proteins also were able to interact with these sites was investigated. the coat proteins of tsv, bmv, cmv, and sbmv recognize specific sites on almv rna 1. the significance of these sites in virus multiplication is discussed. no specific binding sites were found with tmv coat protein or t ...	1985	18639837
effect of dinucleotides on wheat germ translation system.	the effect of ribodinucleoside monophosphates on total protein synthesis was studied in a wheat germ cell-free system, using brome mosaic virus (bmv) rna as a messenger. dinucleotides inhibit total protein synthesis to different extents. of those tested the most inhibitory is cpa. the inhibitory effect of dinucleotides is due to their adverse effect on initiation and not on elongation of polypeptide synthesis. it seems that the dinucleotides complementary to the initiation codon are able to comp ...	1985	3987903
incomplete polypeptides are formed in vitro by premature chain termination.	the mechanism of incomplete polypeptides formation during protein synthesis was studied in the wheat germ cell-free system programmed with brome mosaic virus rna 4. the synthesis of coat protein, the complete product of rna 4 translation, was accompanied by the appearance of polypeptides of lower molecular mass. it was shown that incomplete products are formed by translation of different lengths of rna 4, always from the first 5' aug codon, and were due neither to proteolysis of coat protein nor ...	1985	4006942
synthesis of brome mosaic virus subgenomic rna in vitro by internal initiation on (-)-sense genomic rna.	the genomes of many (+)-stranded rna viruses, including plant viruses and alphaviruses, consist of polycistronic rnas whose internal genes are expressed via subgenomic messenger rnas. the mechanism(s) by which these subgenomic mrnas arise are poorly understood. based on indirect evidence, three models have been proposed: (1) internal initiation by the replicase on the (-)-strand of genomic rna, (2) premature termination during (-)-strand synthesis, followed by independent replication of the subg ...	1985	3838107
deletions in the 3'-terminal trna-like structure of brome mosaic virus rna differentially affect aminoacylation and replication in vitro.	deletions in cdna clones covering the 3' 201 nucleotides of brome mosaic virus rna 3 were produced by s1 nuclease treatment of cloned dna linearized at several different restriction sites. transcription of these clones yielded rnas containing structural alterations in the 3'-terminal trna-like structure that is involved in aminoacylation and replication. replicase template activity, but not aminoacylation activity, was especially sensitive to deletions in arm c, which contains a tyrosyl anticodo ...	1985	3862087
the replication of plant virus rna.	the roles of plant-encoded rna-dependent rna polymerases and viral rna replicases in the replication of plant viral rna are reviewed with respect to the positive single-stranded tymv, cpmv and bmv.	1985	3940008
nucleotide sequence of cucumber mosaic virus rna. 1. presence of a sequence complementary to part of the viral satellite rna and homologies with other viral rnas.	the nucleotide sequence of the 3389 residues of rna 1 (mr 1.15 x 10(6) of the q strain of cucumber mosaic virus (cmv) was determined, completing the primary structure of the cmv genome (8617 nucleotides). cmv rna 1 was sequenced by the dideoxy-chain-termination method using m13 clones carrying rna 1 sequences as well as synthetic oligonucleotide primers on rna 1 as a template. at the 5' end of the rna there are 97 noncoding residues between the cap structure and the first aug (98-100), which is ...	1985	4018086
sindbis virus proteins nsp1 and nsp2 contain homology to nonstructural proteins from several rna plant viruses.	although the genetic organization of tobacco mosaic virus (tmv) differs considerably from that of the tripartite viruses (alfalfa mosaic virus [almv] and brome mosaic virus [bmv]), all of these rna plant viruses share three domains of homology among their nonstructural proteins. one such domain, common to the almv and bmv 2a proteins and the readthrough portion of tmv p183, is also homologous to the readthrough protein nsp4 of sindbis virus (haseloff et al., proc. natl. acad. sci. u.s.a. 81:4358 ...	1985	3968720
antigenic and biochemical analysis of gb of herpes simplex virus type 1 and type 2 and of cross-reacting glycoproteins induced by bovine mammillitis virus and equine herpesvirus type 1.	an antiserum was produced to the oligomeric form of glycoprotein b (gb) induced by herpes simplex virus type 1 (hsv-1) strain 17. this antiserum gave a single common precipitin line in agar gel immunodiffusion with hsv-1, hsv-2, bovine mammillitis virus (bmv) and equine herpesvirus type 1 (ehv-1). it also neutralized hsv-1, hsv-2 and bmv but not ehv-1. absorption of the antiserum with excess hsv-2 or bmv antigen resulted in an hsv-1-specific neutralizing antiserum. in immunoprecipitation, two pr ...	1985	2981966
genetic recombination between rna components of a multipartite plant virus.	genetic recombination of dna is one of the fundamental mechanisms underlying the evolution of dna-based organisms and results in their diversity and adaptability. the importance of the role of recombination is far less evident for the rna-based genomes that occur in most plant viruses and in many animal viruses. rna recombination has been shown to promote the evolutionary variation of picornaviruses, it is involved in the creation of defective interfering (di) rnas of positive- and negative-stra ...	1986	2423879
identification of regions of brome mosaic virus coat protein chemically cross-linked in situ to viral rna.	rna-protein cross-links were introduced into brome mosaic virus in situ by using the heterobifunctional agent p-azidophenylglyoxal. an improved rna isolation method, without phenol extraction, was used to isolate rna cross-linked with protein. rna of the covalently linked complex was acid-digested and the oligonucleotides still attached to protein were 5'-end-labelled with 32p. the complexes were digested with trypsin and the tryptic peptides were purified by reversed-phase high-performance liqu ...	1986	3943527
the common 5' terminal sequence on trypanosome mrnas: a target for anti-messenger oligodeoxynucleotides.	several mature mrnas of trypanosoma brucei were previously shown to have a common 5' terminal sequence of 35 nucleotides (nt) encoded by a separate mini-exon. to verify whether all trypanosome mrnas contain this mini-exon sequence at their 5' end, we have tested oligodeoxynucleotides complementary to different parts of the 35 nt leader sequence for their ability to inhibit translation of total trypanosome mrna. all oligomers tested inhibited translation of trypanosome mrnas in a wheat germ extra ...	1986	3737413
minus-strand initiation by brome mosaic virus replicase within the 3' trna-like structure of native and modified rna templates.	an rna-dependent rna polymerase (replicase) extract from brome mosaic virus-infected barley leaves has been shown to initiate synthesis of (-) sense rna from (+) sense virion rna. initiation occurred de novo, as demonstrated by the incorporation of [gamma-32p]gtp into the product. sequencing using cordycepin triphosphate to terminate (-) strands during their synthesis by the replicase generated sequence ladders that confirmed that copying was accurate, and that initiation occurred very close to ...	1986	3754904
modulation of replication, aminoacylation and adenylation in vitro and infectivity in vivo of bmv rnas containing deletions within the multifunctional 3' end.	the genome of brome mosaic virus (bmv) is comprised of three (+) strand rnas, each containing a similar, highly structured, 200 base long sequence at its 3' end. a 134 base subset of this sequence contains signals directing interaction of the viral rna with bmv rna replicase, atp,ctp:trna nucleotidyl transferase and aminoacyl trna synthetase. a series of mutants containing deletions within this region, previously constructed and tested in vitro for the effect on replication and aminoacylation ac ...	1986	3758026
swelling of isometric and of bacilliform plant virus nucleocapsids is required for virus-specific protein synthesis in vitro.	encapsidated rna of cowpea chlorotic mottle virus (ccmv), brome mosaic virus (bmv), alfalfa mosaic virus, and southern bean mosaic virus can act as templates for protein synthesis when preswollen virions are added to a wheat germ extract, or when unswollen virions swell in the extract. encapsidated rna of turnip yellow mosaic virus, whose particles are unlikely to swell under the conditions used here, did not act as a template. ccmv and bmv, swollen in the extract, gave relatively more rna 1 and ...	1986	18640565
bacterial gene inserted in an engineered rna virus: efficient expression in monocotyledonous plant cells.	brome mosaic virus (bmv) is a plant virus whose genome consists of three rna components. a previously described viral complementary dna expression system has been used to express both wild-type and altered genomic rna's in barley protoplasts. variants of bmv rna3 were constructed in which the coat gene had been removed or replaced with sequences encoding chloramphenicol acetyltransferase (cat). cat sequences were also inserted near the 5' end of the intact coat gene. when inoculated on protoplas ...	1986	17839568
inoculation of protoplasts with viruses by electroporation.	optimal conditions for electroporation have been determined using inoculation of brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) and its rna into protoplasts of nicotiana tabacum and n. plumbaginifolia. the most satisfactory medium was 0.5-0.7 m mannitol; calcium ions were toxic and other electrolytes were not helpful during electroporation. brief pulses (ca. 10 microsec) were less destructive to the protoplasts than longer ones (ca. 10 msec) and gave high percentage infections ...	1987	18644555
brome mosaic virus coat protein inhibits viral rna synthesis in vitro.	in vitro, the coat protein of brome mosaic virus (bmv) inhibited rna synthesis by replicase extracted from bmv-infected barley leaves. the inhibition was due to the interaction of coat protein with bmv rna. under the same conditions, no inhibition by tmv coat protein or bovine serum albumin was detected. for the complete inhibition of rna synthesis in vitro, a coat protein:rna ratio of 620:1 was required, and their preincubation before addition to the reaction mixture was essential. if the coat ...	1987	18644560
high efficiency t7 polymerase synthesis of infectious rna from cloned brome mosaic virus cdna and effects of 5' extensions on transcript infectivity.	addition of a single extra 5' g residue reduces the infectivity of transcripts from cloned bmv cdna no more than threefold, while addition of 7- or 16-base 5' extensions to rna3 transcripts dramatically suppresses their biological activity. moreover, despite resultant alteration of the promoter consensus sequence, fusion of bmv cdna directly to the initiation site of the canonical phi10 promoter of bacteriophage t7 allows efficient in vitro synthesis of infectious bmv transcripts by t7 rna polym ...	1987	18644564
longidorus breviannulatus as a vector for brome mosaic virus.		1987	19290121
intercistronic as well as terminal sequences are required for efficient amplification of brome mosaic virus rna3.	the genome of brome mosaic virus (bmv) is divided among messenger polarity rna1, rna2, and rna3 (3.2, 2.9, and 2.1 kilobases, respectively). cis-acting sequences required for bmv rna amplification were investigated with rna3. by using expressible cdna clones, deletions were constructed throughout rna3 and tested in barley protoplasts coinoculated with rna1 and rna2. in contrast to requirements for 5'- and 3'-terminal noncoding sequences, either of the two rna3 coding regions can be deleted indiv ...	1987	3573144
role of bovine mammillitis virus towards preparation of an alternative vaccine against herpes simplex virus infections of human subjects.	bovine mammillitis virus (bmv) cross-reacted in neutralization and radioimmune assay with herpes simplex virus (hsv) and pre-immunization with bmv protected against challenge by type 2 hsv. there was no evidence to suggest a pathogenic role for bmv as adjudged by a literature search or field enquiry and bmv specific antibody was not detected in 21 human sera or in four sera from personnel engaged in research with bmv; in addition there was no replication or antigen synthesis by bmv in explants o ...	1987	3033927
molecular studies of brome mosaic virus using infectious transcripts from cloned cdna.		1987	3303861
analysis of brome mosaic virus replication and aminoacylation functions by site-specific mutagenesis.	brome mosaic virus (bmv) has a tripartite rna genome; each rna and the subgenomic rna encoding the viral coat protein share a highly homologous region of about 200 nucleotides at the 3' end, for which a trna-like structure has been proposed. several sequences encoding functions, including replicase binding, initiation of (-) strand synthesis and tyrosine esterification are known to be nested within this region. elongation factor ef-1 alpha binds to aminoacylated viral rnas, but not to the unchar ...	1987	3503887
[site-specific cleavage of rna 3 from brome mosaic virus in the intercistron region and restoration of the internal poly(a)-track in a progeny of religated rna].		1988	2844489
mutational analysis of the core and modulator sequences of the bmv rna3 subgenomic promoter.	the subgenomic promoter of a (+)-stranded rna virus, brome mosaic virus (bmv) controlling synthesis of subgenomic rna4 has been defined in vitro. truncated and mutant (-)-strand rna templates were produced by in vitro transcription of cloned rna3 cdna. subgenomic (+)-sense rna was synthesized in vitro from these templates by a replicase (rna-dependent rna polymerase) preparation extracted from infected barley leaves. the activities of templates with truncations and deletions surrounding the rna4 ...	1988	2830598
pressure-induced dissociation of brome mosaic virus.	brome mosaic virus reversibly dissociates into subunits in the pressure range of 600 x 10(5) to 1600 x 10(5) pa, as demonstrated by studies of the spectral shift of intrinsic fluorescence, of filtration chromatography and of electron microscopy of samples fixed under pressure. smaller shell particles (t = 1) were detected as intermediates in the dissociation pathway. dissociation was facilitated by decreasing the concentration, as expected for a multimolecular reaction. the estimated change in v ...	1988	3351916
characterization and engineering of sequences controlling in vivo synthesis of brome mosaic virus subgenomic rna.	expression of brome mosaic virus (bmv) coat protein and internal genes of many other positive-strand rna viruses requires initiation of subgenomic mrna synthesis from specific internal sites on minus-strand genomic rna templates. biologically active viral cdna clones were used to investigate the sequences controlling production of bmv subgenomic rna in vivo. suitable duplications directed production of specifically initiated, capped subgenomic rnas from new sites in the bmv genome. previously im ...	1988	3373573
complementary oligodeoxynucleotide mediated inhibition of tobacco mosaic virus rna translation in vitro.	two different "antisense" oligodeoxynucleotides and their rna analogues, each complementary to non-overlapping sequences of 51 bases near the 5' end of tmv rna, inhibit in vitro translation of the genomic rna in a rabbit reticulocyte lysate. inhibition is dependent upon complementarity, concentration, and hybridization of the oligomers with tmv rna. inhibition is observed at molar ratios of tmv rna to antisense oligomers as low as 1:1.5. a plateau of inhibition at which 10-25% of the control sig ...	1988	3380688
further implications for the evolutionary relationships between tripartite plant viruses based on cucumber mosaic virus rna 3.	the nucleotide sequence of the rna 3 of the q-strain of cucumber mosaic virus (q-cmv) has been reinvestigated and supporting partial amino acid sequence data obtained for the coat protein. corrections to the previously published sequence of rna 3 [a. r. gould and r. h. symons (1982) eur. j. biochem. 126, 217-226] result in changes to the size and composition of the putative 3a and coat proteins. analysis of the nucleotide sequence revealed a 14-nucleotide sequence present in the intercistronic r ...	1988	3388769
a continuous cell-free translation system capable of producing polypeptides in high yield.	a cell-free translation system has been constructed that uses a continuous flow of the feeding buffer [including amino acids, adenosine triphosphate (atp), and guanosine triphosphate (gtp)] through the reaction mixture and a continuous removal of a polypeptide product. both prokaryotic (escherichia coli) and eukaryotic (wheat embryos, triticum sp.) versions of the system have been tested. in both cases the system has proven active for long times, synthesizing polypeptides at a high constant rate ...	1988	3055301
the nucleotide sequence and gene organization of red clover necrotic mosaic virus rna-2.	red clover necrotic mosaic virus, a member of the dianthovirus group, is characterized by a genome composed of two nonhomologous single-stranded rnas of approximately 4.0 (rna-1) and 1.4 kb (rna-2). the complete nucleotide sequence of the rna-2 has been determined. rna-2 is 1448 nucleotides in length with a 5' terminal m7g cap and no 3' terminal poly-a tail or 5' terminal vpg. an open reading frame beginning at the first initiation codon at nucleotide 80 and ending at nucleotide 1030 has been id ...	1988	3047682
hybrid brome mosaic virus rnas express and are packaged in tobacco mosaic virus coat protein in vivo.	brome mosaic virus (bmv) is an icosahedral virus with a tripartite rna genome which infects monocotyledonous plants, while the cowpea or legume strain of tobacco mosaic virus (cctmv) is a rod-shaped virus with a single component rna genome which infects dicotyledonous plants. to examine the potential for exchanging entire genes between rna viruses, biologically active cdna clones were used to replace the natural coat gene of bmv rna3 with the coat gene and encapsidation origin of cctmv. in proto ...	1988	2847411
mutational analysis of the trna mimicry of brome mosaic virus rna. sequence and structural requirements for aminoacylation and 3'-adenylation.	the genomic rnas of brome mosaic virus (bmv) exhibit various trna-like properties, including specific tyrosylation by tyrosyl-trna synthetases and adenylation of the 3'-ccoh derivative by trna nucleotidyl transferases. we have studied the effect of numerous mutations in all domains of the trna-like structure of bmv rna on tyrosylation and adenylation in vitro. surprisingly few mutations resulted in more than 50% decrease in tyrosylation rates with either wheat germ or yeast synthetases; those mu ...	1988	3418699
studies on the mechanism of translational enhancement by the 5'-leader sequence of tobacco mosaic virus rna.	translation of foreign mrnas is enhanced by a cis-acting derivative (omega') of the 5'-leader sequence (omega) of tobacco mosaic virus rna (vulgare strain). to explain this effect we have conducted several experiments in vitro. 1. the presence of various 5'-terminal sequences, including omega', did not significantly increase the half-lives of chloramphenicol acetyltransferase (cat) or neomycin phosphotransferase (nptii) mrnas in wheat-germ extract. also, a long leader sequence, unrelated to omeg ...	1988	2841127
reduced tumorigenicity of rodent tumour cells and tumour explants following infection with wild type and mutant herpes simplex virus, bovine mammillitis virus and encephalomyocarditis virus.	the tumorigenicity of neoplastic hamster and mouse cell lines and tumour explants was reduced by infection with herpes simplex virus (hsv-1), a thymidine-kinaseless mutant of herpes simplex virus, namely 'mdk', encephalomyocarditis virus (emc) and bovine mammillitis virus (bmv). there was an approximate relationship between duration of virus infection in vitro and reduction in incidence and/or rate of tumour development. the rate of tumour development was also reduced by 'site inoculation' of vi ...	1988	2846027
hemolysates from guinea-pig reticulocytes also efficiently translate added mrna.	1. lysate is prepared from guinea-pig reticulocytes and its translation activity is compared both quantitatively and qualitatively with that found in rabbit reticulocyte lysates. 2. guinea-pigs are comparatively resistant to acetylphenylhydrazine, a drug used to induce reticulocytosis in rabbits. 3. the characteristics and conditions for maximal translation activity in guinea-pig reticulocyte lysates are quite similar to those described for rabbit reticulocyte systems with the possible exception ...	1988	3197393
mutational analysis of the sequence and structural requirements in brome mosaic virus rna for minus strand promoter activity.	an rna-dependent rna polymerase (replicase) activity that specifically copies brome mosaic virus (bmv) rnas in vitro can be prepared from bmv-infected barley leaves. the signals directing complementary (minus) strand synthesis reside within the 3' 134-nucleotide-long trna-like structure that is common to each of the virion rnas. by studying the influence of minus strand synthesis of numerous mutations introduced throughout this region of the rna, we have mapped in detail the sequence and structu ...	1988	3418698
infectious in vitro transcripts from cowpea chlorotic mottle virus cdna clones and exchange of individual rna components with brome mosaic virus.	complete cdna copies of genomic rna1, rna2, and rna3 of cowpea chlorotic mottle virus (ccmv) were cloned 1 base downstream from a t7 rna polymerase promoter. the mixture of capped in vitro transcripts from all three clones produced normal ccmv infections in barley protoplasts and cowpea plants. by using transcripts from these clones and from a similar set of biologically active clones of the related brome mosaic virus (bmv), all possible single component exchanges between the bmv and ccmv tripar ...	1988	3418781
a neurospora crassa heat-shocked cell lysate translates homologous and heterologous messenger rna efficiently, without preference for heat shock messages.	cell-free protein synthesis systems were prepared from normally-grown (n-lysate) and heat-shocked (hs-lysate) neurospora crassa mycelium. although both lysates translated homologous mrna, the hs-lysate was more active, yielding a higher incorporation of [35s]-methionine into hot tca-insoluble material and a vastly superior protein synthesis profile. the optimal temperature for translation by both lysates was 21 degrees c; the hs-lysate did not translate heat-shock mrna preferentially at any temp ...	1988	2969781
involvement of a nonstructural protein in the rna synthesis of brome mosaic virus.	rna-dependent rna polymerase (rdrp) was prepared from brome mosaic virus (bmv)-infected barley by a procedure including nonidet-p40 treatment. the enzyme proved to be highly active, specific, and almost completely template dependent without the need for nuclease treatment [w. a. miller, and t. c. hall (1983) virology 125, 236-241] or deae ion exchange chromatography [k. maekawa and i. furusawa (1984) ann. phytopathol. soc. japan 50, 491-499]. two c-terminal peptides p1c and p2c derived from the ...	1988	3388771
identification and characterization of maize pathogenesis-related proteins. four maize pr proteins are chitinases.	eight pathogenesis-related proteins extractable at ph 2.8 were found to accumulate in maize leaves after mercuric chloride treatment or brome mosaic virus infection. these proteins were called prm (pathogenesis-related maize) proteins. seven prm proteins were purified to homogeneity by preparative polyacrylamide gel electrophoresis and their amino acid compositions determined. estimated molecular weights in sds-containing gels were: prm 1 14.2 kda; prm 2 16.5 kda; prm 3 and prm 4 25 kda; prm 6b ...	1988	24272409
chloroplast import characteristics of chimeric proteins.	we have examined the import of a series of chimeric precursor proteins into chloroplasts. these fusion proteins contained the transit peptide, and various amounts of the amino-terminal region of the mature peptide, from the small subunit of ribulose 1,5-bisphosphate carboxylase, linked to the coat protein of brome mosaic virus. chimeric genes were cloned into sp6 plasmids and in vitro transcription/translation was used to produce fusion proteins, which were examined in a quantitative in vitro im ...	1989	24272713
defined mutations in a small region of the brome mosaic virus 2 gene cause diverse temperature-sensitive rna replication phenotypes.	the central portion of the brome mosaic virus (bmv) 2a protein represents the most conserved element among the related rna replication components of a large group of positive-strand rna viruses of humans, animals, and plants. to characterize the functions of the 2a protein, mutations were targeted to a conserved portion of the 2a gene, resulting in substitutions between amino acids 451 and 484. after the temperature profile of wild-type bmv rna replication was defined, rna replication by nine se ...	1989	2585606
partial purification and characterization of a formylmethionine deformylase from rat small intestine.	a formylmethionine deformylase from rat small-intestinal mucosa has been isolated, characterized and partially purified. the enzyme catalyses the release of equimolar amounts of formate and the free amino acid. the deformylase was active against formylmethionine (km 7.1 mm) and formylnorleucine, but showed reduced activity against formyl-leucine. it was inactive against a range of other polar and nonpolar formyl-amino acids and against formyl di- and tri-peptides. the mr of the native enzyme was ...	1989	2920026
hemin and cyclic amp stimulate message-dependent translation in lysates from friend erythroleukemia cells.	a message-dependent, cell-free translation system was prepared from both uninduced and n,n'-hexamethylene-bis-acetamide-induced friend erythroleukemia cells following modification of standard protocols. active extracts were prepared by lysing friend erythroleukemia cells in hypotonic buffer containing 50 microm hemin and 10 mm cyclic adenosine monophosphate (camp), and assaying translation in vitro in the absence of exogenous nucleoside triphosphates. both hemin and camp were required for full a ...	1989	2541008
structural analogies between the 3' trna-like structure of brome mosaic virus rna and yeast trnatyr revealed by protection studies with yeast tyrosyl-trna synthetase.	contacts between the trna-like domain in brome mosaic virus rna and yeast tyrosyl-trna synthetase have been determined by footprinting with enzymatic probes. regions in which the synthetase caused protections indicative of direct interaction coincide with loci identified by mutational studies as being important for efficient tyrosylation [dreher, t. w. & hall, t. c. (1988) j. mol. biol. 201, 41-55]. additional extensive contacts were found upstream of the core of the trna-like structure. in para ...	1989	2684668
replication in vivo of mutant brome mosaic virus rnas defective in aminoacylation.	in order to understand the relationship between replication and aminoacylation of the genomic rnas of brome mosaic virus, the replication of four mutants, whose rnas were expected (on the basis of their properties in vitro) to be inefficiently tyrosylated in vivo, was studied in barley protoplasts and plants. test inocula consisted of capped transcripts of wild-type rnas 1 and 2, and of rna 3 variants with defined mutations in the 3' trna-like region. mutant 5'psk, which is defective in minus-st ...	1989	2716056
nucleotide sequence and translation of satellite tobacco mosaic virus rna.	satellite tobacco mosaic virus (stmv) is a plant virus with a 17-nm icosahedral particle encapsidating a 0.3 x 10(6) mr ssrna genome that depends on tobamoviruses for its replication. the complete nucleotide sequence of stmv rna deduced in the experiments described here was 1059 nucleotides in length. the efficiency of labeling viral rna with [gamma-32p]atp using t4 polynucleotide kinase was not affected by treatment with tobacco acid pyrophosphatase and/or bacterial alkaline phosphatase, indica ...	1989	2718378
derivation of an infectious viral rna by autolytic cleavage of in vitro transcribed viral cdnas.	an in vitro transcription system has been developed that utilizes self-processing to adjust 3' termini in transcribed viral rnas. transcription vectors were constructed by ligating a cdna "cassette" containing self-cleavage sequences from the satellite rna of tobacco ringspot virus (stobrv rna) with the 3' end of brome mosaic virus (bmv) cdna clones. transcripts were obtained either from templates linearized at positions located downstream from the cassette or from nonlinearized plasmids. in bot ...	1989	2740329
telomeric function of the trna-like structure of brome mosaic virus rna.	four mutant brome mosaic virus (bmv) rna3 transcripts, bearing single or double base changes in the 3'-ccaoh terminus of the trna-like structure, previously characterized as being deficient in vitro with respect to aminoacylation and replication activities, have now been assayed in vivo for their ability to replicate (in the presence of transcripts of wild-type rna1 and -2) in barley protoplasts and plants. in tests conducted with protoplasts, irrespective of the time post-infection, all four mu ...	1989	2748589
sequence of cowpea chlorotic mottle virus rnas 2 and 3 and evidence of a recombination event during bromovirus evolution.	the genomic sequence of cowpea chlorotic mottle virus (ccmv) was completed by sequencing biologically active cdna clones of ccmv rna2 (2774 bases) and rna3 (2173 bases). while only the central core of the encoded 94-kda ccmv 2a protein contains features conserved among known and putative rna replication proteins from many viruses, both flanking regions of ccmv 2a show substantial similarity to the corresponding protein of the related brome mosaic virus (bmv). the 3a proteins of ccmv and bmv, imp ...	1989	2773323
effects of deletions in the n-terminal basic arm of brome mosaic virus coat protein on rna packaging and systemic infection.	the first 25 amino acids of brome mosaic virus (bmv) coat protein include 8 basic and no acidic residues and are implicated in binding the encapsidated rna. using infectious transcripts from bmv rna3 cdna clones, we modified this region of the coat gene. a coat protein mutant with the first 25 amino acids deleted failed to direct either packaging of viral rna in protoplasts or systemic infection of whole barley plants. neither symptoms, virions, nor viral rna was detectable in plants inoculated ...	1989	2795712
similarities among plant virus (+) and (-) rna termini imply a common ancestry with promoters of eukaryotic trnas.	the 5' ends of brome mosaic virus (bmv) rnas contain sequences similar to the consensus internal control region (icr) of pol iii promoters in trna genes. comparison of bmv (+)rna 5' termini with bmv (-)rna termini revealed the presence of two (tandem) repeats of some 30 nucleotides, the more internal containing a region of 73% similarity to the trna consensus icr2 (downstream) region of the icr. tandem repeats containing motifs similar to the icr2 consensus were found at the 5' termini of (-)rna ...	1989	2800331
search of essential parameters for the aminoacylation of viral trna-like molecules. comparison with canonical transfer rnas.	comparative structural and functional results on the valine and tyrosine accepting trna-like molecules from turnip yellow mosaic virus (tymv) and brome mosaic virus (bmv), and the corresponding cognate yeast trnas are presented. novel experiments on tymv rna include design of variant genes of the trna-like domain and their transcription in vitro by t7 rna polymerase, analysis of their valylation catalyzed by yeast valyl-trna synthetase, and structural mapping with dimethyl sulfate and carbodiimi ...	1990	2207141
analysis of the role of brome mosaic virus 1a protein domains in rna replication, using linker insertion mutagenesis.	brome mosaic virus (bmv) belongs to a "superfamily" of plant and animal positive-strand rna viruses that share, among other features, three large domains of conserved sequence in nonstructural proteins involved in rna replication. two of these domains reside in the 109-kda bmv 1a protein. to examine the role of 1a, we used biologically active cdna clones of bmv rna1 to construct a series of linker insertion mutants bearing two-codon insertions dispersed throughout the 1a gene. the majority of th ...	1990	2243389
analysis of rna stability and (-) strand content in viral infections using biotinylated rna probes.	non-radioactive biotinylated rna probes specific for plus (+) and minus (-) sense rnas of brome mosaic virus (bmv) were synthesized in vitro from a plasmid bearing a 200 base pair fragment complementary to the 3' terminus of each of the three genomic rnas of the virus. using virion rnas isolated from bmv infected barley plants, the sensitivity of biotinylated rnas as hybridization probes was compared with that of 32p-labeled probes in northern hybridization assays. although the sensitivity of bi ...	1990	1707891
frog virus 3-mediated translational shut-off: frog virus 3 messages are translationally more efficient than host and heterologous viral messages under conditions of increased translational stress.	frog virus 3 rapidly and selectively blocks host cell translation while synthesizing more than 60 virus-specific polypeptides. previous work indicated that virus infection led to activation of a kinase that phosphorylated and, as a consequence, inactivated eif-2. although phosphorylation of eif-2 could explain the rapid decline in host cell translation, it could not explain how viral protein synthesis persisted in the face of host shut-off. to explain this phenomenon, we speculated that viral me ...	1990	2201134
use of bromovirus rna2 hybrids to map cis- and trans-acting functions in a conserved rna replication gene.	brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) are related positive-strand rna viruses with tripartite genomes. rna replication by either virus requires genomic rnas 1 and 2, which encode protein 1a and the polymeraselike, 94-kilodalton 2a protein, respectively. proteins 1a and 2a share extensive sequence similarity with proteins encoded by a wide range of other positive-strand rna viruses of animals and plants. heterologous combinations of bmv and ccmv rnas 1 and 2 do not sup ...	1990	2293671
cis-acting sequences required for in vivo amplification of genomic rna3 are organized differently in related bromoviruses.	cowpea chlorotic mottle virus (ccmv) is a positive-strand rna virus that infects dicotyledonous plants. the genome comprises three capped rnas: rna1 (3.2 kb), rna2 (2.9 kb), and rna3 (2.1 kb). cis-acting sequences required for amplification in vivo were explored for rna3, which does not contribute trans-acting factors to viral rna replication. using a ccmv cdna expression system, deletions throughout rna3 were constructed and tested for successful replication in barley protoplasts coinoculated w ...	1990	2305551
requirement for a viral trans-acting factor encoded by brome mosaic virus rna-2 provides strong selection in vivo for functional recombinants.	interaction of specific nucleotide sequences with trans-acting proteins is intrinsic to replication of viral as well as eucaryotic genomes. brome mosaic virus rna-2 encodes one of the two viral proteins known to be essential for replication. (r. french, m. janda, and p. ahlquist, science 231:1294-1297, 1986; p. a. kiberstis, l. s. loesch-fries, and t. c. hall, virology 112:804-808, 1981). transfection of barley protoplasts with wild-type transcripts of brome mosaic virus rna-1 and rna-3 and seri ...	1990	2325208
use of chenopodium hybridum facilitates isolation of brome mosaic virus rna recombinants.	three mutant brome mosaic virus (bmv) rna-2 transcripts bearing two alterations in the pseudoknot region and one in arm c of the 3' trna region, previously characterized as being deficient in trna-like functions, have been assayed for their ability to infect and replicate (in the presence of wild-type rnas-1 and -3) in chenopodium hybridum plants. although the introduced mutations have been shown to incapacitate the replication of rna-2 in barley protoplasts, c. hybridum plants inoculated with t ...	1990	2351959
point mutations in the icr2 motif of brome mosaic virus rnas debilitate (+)-strand replication.	sequences at the 5' termini of the genomic rnas of brome mosaic virus (bmv) and other (+)-stranded rna viruses have been shown (l.e. marsh and t.c. hall, 1987, cold spring harbor symp. quant. biol. 52, 331-341) to resemble the icrs 1 and 2 (a and b boxes) of trna genes, with the complementary sequences at the 3' termini of the (-) strands resembling the icr2 motif of methionine initiator trna genes (l.e. marsh, g.p. pogue, and t.c. hall, 1989, virology 172, 415-427). in order to examine the role ...	1990	2389549
purification and characterization of brome mosaic virus rna-dependent rna polymerase.	rna-dependent rna polymerase (rdrp) was solubilized from cellular membranes of brome mosaic virus (bmv)-infected barley. the solubilized enzyme was subsequently purified by glycerol gradient centrifugation and deae ion-exchange chromatography. the purified enzyme proved to be highly stable and both dependent on and specific for bmv rnas. the enzyme is inhibited by high template rna concentrations. this inhibition indicates feedback regulation of minus-strand synthesis. the nonstructural viral pr ...	1990	2389551
a virus-particle vaccine prepared from bovine mammillitis virus against herpes genitalis.	a vaccine against herpes genitalis was prepared from the extracellular virus particles from baby hamster kidney cells infected with bovine mammillitis virus (bmv) strain "allerton". the virus was inactivated by formaldehyde followed by ultracentrifugation to concentrate the virus particles and eliminate formaldehyde to an acceptable concentration for immunisation of human subjects. the vaccine was cross antigenic and cross immunogenic with herpes simplex virus type 1. thirty-four consorts at hig ...	1991	1657508
deletion analysis of brome mosaic virus 2a protein: effects on rna replication and systemic spread.	brome mosaic virus (bmv) genomic rna2 encodes the 94-kda 2a protein, which is one of two bmv nonstructural proteins required for rna replication and subgenomic mrna transcription. 2a contains a central polymeraselike region, which has extensive sequence similarity with the sindbis virus nsp4 and tobacco mosaic virus (tmv) 183-kda replication proteins, and also contains n- and c-terminal flanking segments without counterparts in the sindbis virus and tmv nonstructural proteins. to further investi ...	1991	2033655
nucleotide sequence of tomato aspermy virus rna 2.	rna 2 of the v strain of tomato aspermy virus (tav) consists of 3074 nucleotides and contains one open reading frame of 2487 nucleotides. thus, it resembles rna 2 of cucumber mosaic virus (cmv) strains q and fny (62% identical to both), brome mosaic virus (42% identical) and cowpea chlorotic mottle virus (40% identical). in comparisons between amino acid sequences, three different regions of similarity could be distinguished. these were the central part (amino acids 224 to 757 for v-tav), which ...	1991	2016592
the interaction of wheat germ tyrosyl-trna synthetase and the trna-like end of brome mosaic virus rna has no effect on in vitro viral protein synthesis and on in vitro encapsidation.	the effect of aminoacylation of the trna-like end of brome mosaic virus rna during in vitro protein synthesis and in vitro viral encapsidation was investigated. the components of the homologous system were: bmv rna, wheat germ cell-free protein synthesizing system and pure tyrosyl-trna synthetase from wheat germ. during in vitro protein synthesis directed with tyrosylated as well as non-tyrosylated bmv rna, no differences were observed in the amount and in the class of polypeptides formed neithe ...	1991	1782218
artificial defective interfering rnas derived from brome mosaic virus.	naturally occurring defective interfering rnas (di-rnas) greatly reduce the accumulation of their helper virus in vivo, but are rarely associated with plant positive-strand rna viruses. deletion mutants prna-2 m/s and prna-2 e/s, derived from brome mosaic virus (bmv) genomic rna-2, replicated in a manner dependent on bmv rna-1 and -2, and effectively interfered with their accumulation in barley protoplasts. based on their mode of replication, these mutant rnas have been termed parasitic rnas (pr ...	1991	1875191
evolutionary relationships in the cucumoviruses: nucleotide sequence of tomato aspermy virus rna 1.	rna 1 of the v strain of tomato aspermy virus (tav) consists of 3410 nucleotides and contains one open reading frame (orf) of 2982 nucleotides, resembling rna 1 of cucumber mosaic virus (cmv) strains q and fny (68% and 66% identical, respectively) and of brome mosaic virus (bmv) (41% identical). in comparisons between amino acid sequences, three conserved regions (n-terminal, c-terminal and central) between tav and each cmv were found. the n- and c-terminal regions were also conserved with bmv, ...	1991	1895056
non-replicating deletion mutants of brome mosaic virus rna-2 interfere with viral replication.	naturally occurring defective interfering rnas (di-rnas) and satellite rnas greatly reduce the accumulation of their helper virus in vivo, but often modulate symptom expression in an unpredictable manner. deletion mutants nc/s, na/m and sa/nc + m/s, derived from brome mosaic virus (bmv) rna-2, failed to replicate when co-inoculated with bmv rnas-1 and -2 to barley protoplasts. however, the inoculum rna corresponding to these deletion mutants was extremely stable and could have been mistaken for ...	1991	1919522
interference in trans with brome mosaic virus replication by rna-2 bearing aminoacylation-deficient mutants.	the trna-like domain present at the 3' end of each of the three genomic rnas of brome mosaic virus (bmv) encompasses the (-)-strand promoter essential for replication. the replicative competence of two bmv rna-2 transcripts bearing mutations delta 5' and 5'aga in the trna-like domain (previously shown by in vitro assays to be deficient in tyrosylation) was evaluated in barley protoplasts. transfection of protoplasts with low (2 micrograms) amounts of delta 5'rna-2, together with transcripts of w ...	1991	1984646
tomato aspermy virus has an evolutionary relationship with other tripartite rna plant viruses.	the entire rna 3 (2214 nucleotides) of a chrysanthemum isolate of tomato aspermy virus (c-tav) has been cloned and its sequence determined. c-tav possesses two open reading frames which encode a 3a protein (277 amino acids) and a coat protein (229 amino acids). computer-assisted comparisons were made between c-tav rna 3 and its predicted protein sequences and those of two other tripartite rna viruses, cucumber mosaic virus (cmv) and brome mosaic virus (bmv). results from this study suggest that ...	1991	1990057
infectivity of plasmids containing brome mosaic virus cdna linked to the cauliflower mosaic virus 35s rna promoter.	full-length biologically active cdnas of brome mosaic virus genomic rnas 1, 2 and 3 were constructed by joining cdna fragments. the cdnas were constructed so that, at the 5' ends, unique snabi sites were present at the site of initiation of transcription. the cdnas were inserted between a modified cauliflower mosaic virus (camv) 35s rna promoter and terminator regions derived from camv dna, and cloned into puc18. when a mixture of the plasmid dnas was inoculated onto chenopodium hybridum leaves, ...	1991	1993867
generation and analysis of nonhomologous rna-rna recombinants in brome mosaic virus: sequence complementarities at crossover sites.	all three single-stranded rnas of the brome mosaic virus (bmv) genome contain a highly conserved, 193-base 3' noncoding region. to study the recombination between individual bmv rna components, barley plants were infected with a mixture of in vitro-transcribed wild-type bmv rnas 1 and 2 and an rna3 mutant that carried a deletion near the 3' end. this generated a population of both homologous and nonhomologous 3' recombinant bmv rna3 variants. sequencing revealed that these recombinants were deri ...	1991	2072447
regulation of (+):(-)-strand asymmetry in replication of brome mosaic virus rna.	transfection of barley protoplasts with brome mosaic virus (bmv) rnas 1 + 2 in the absence of rna-3 yielded a molar ratio for (+):(-)-strand progeny at 24 hr postinoculation near unity, whereas over 100-fold more (+)- than (-)-strand progeny accumulated in its presence. the presence of rna-3 enhanced total (+)-strand rna production 205-fold and that of rnas 1 + 2 by 29-fold. in contrast, total (-)-strand rna accumulation decreased by 68% and that for (-)rnas 1 + 2 by 79% in the presence of rna-3 ...	1991	2024481
turnip yellow mosaic virus rnas with anticodon loop substitutions that result in decreased valylation fail to replicate efficiently.	single and multiple nucleotide substitutions have been introduced into the anticodon loop of the trna-like structure of turnip yellow mosaic virus (tymv) genomic rna. we studied the effects of these mutations on in vitro valylation and on replication in chinese cabbage protoplasts and plants. only those mutants capable of efficient and complete valylation showed efficient replication in protoplasts and gave rise to systemic symptoms in whole plants. mutants that accepted valine inefficiently (in ...	1991	2033666
biological activities of hybrid rnas generated by 3'-end exchanges between tobacco mosaic and brome mosaic viruses.	sequences within the conserved, aminoacylatable 3' noncoding regions of brome mosaic virus (bmv) genomic rnas 1, 2, and 3 direct initiation of negative-strand synthesis by bmv polymerase extracts and, like sequences at the structurally divergent but aminoacylatable 3' end of tobacco mosaic virus (tmv) rna, are required in cis for rna replication in vivo. a series of chimeric rnas in which selected 3' segments were exchanged between the tyrosine-accepting bmv and histidine-accepting tmv rnas were ...	1991	2041076
use of bromovirus rna3 hybrids to study template specificity in viral rna amplification.	brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) are related positive-strand rna viruses with genomes divided among rnas 1, 2, and 3. rnas 1 and 2 encode the viral rna replication factors, which share extensive conservation with proteins encoded by the animal alphaviruses and diverse plant viruses. in barley protoplasts, ccmv rnas 1 and 2 support high but distinguishable amplification of either bmv rna3 (b3) or ccmv rna3 (c3), while bmv rnas 1 and 2 show even greater discriminat ...	1991	2041089
analysis of the protein composition of alfalfa mosaic virus rna-dependent rna polymerase.	rna-dependent rna polymerase (rdrp) was solubilized and purified from cellular membranes isolated from alfalfa mosaic virus (aimv)-infected tobacco by employing a procedure recently described for brome mosaic virus rdrp [r. quadt and e.m.j. jaspars, 1990, virology 178, 189-194]. the purified aimv rdrp is completely dependent on added template rnas and exhibits a high degree of template specificity. analysis of the protein composition of aimv rdrp showed that aimv-encoded proteins p1 and p2 and t ...	1991	2024468
molecular design of a eukaryotic messenger rna and its chemical synthesis.	a designed mrna consisting of 42 ribonucleotides having the cap structure was synthesized. the capped leader sequence of the brome mosaic virus (bmv) mrna 4, m7g5'pppguauuaaua (f-1), was synthesized by the phosphotriester method and followed by the capping reaction. a 32-mer consisting of an initiation codon (aug), the coding region corresponding to a bacterial pheromone cad1 and two stop codons, was constructed by the 18-mer (f-2) and 14-mer (f-3), which were synthesized by the phosphoramidite ...	1992	1374557
exogenous primer-independent cdna synthesis with commercial reverse transcriptase preparations on plant virus rna templates.	upon reverse transcription and cloning manipulations with virion rnas of several plant viruses, namely beet yellows virus, brome mosaic virus, and potato virus x, we came across a significant background synthesis of cdna on the virion rna template in vitro independent of exogenous primers added. when tested with beet yellow virus rna template, several commercial preparations of avian myeloblastosis virus (amv) reverse transcriptase showed the background activity monitored by the [alpha-32p]dntp ...	1992	1381874
genetic recombination in brome mosaic virus: effect of sequence and replication of rna on accumulation of recombinants.	in order to facilitate the isolation of recombinants in brome mosaic virus, a series of duplication mutants with alterations in the rna3 3' noncoding region has been engineered. the distribution of crossovers, which was observed to be dependent on the parental rna3 sequence, supported the role of rna structure in recombination. however, a negative correlation between replication of the parental rna3 constructs and the accumulation of recombinant progeny confirmed the role of selection.	1992	1404621
the requirement for a 5' stem-loop structure in brome mosaic virus replication supports a new model for viral positive-strand rna initiation.	sequences with strong similarity to internal control regions 1 and 2 (icr1 and -2; a and b boxes) of trna genes are found at the 5' termini of the genomic rnas of brome mosaic virus (bmv) and other plant viruses. the functionality of these motifs was studied by introducing point mutations into the icr2-like sequence of prna-2 m/s, a bmv rna-2 deletion mutant that replicates in the presence of rnas-1 and -2 but does not encode a functional viral protein. the accumulation of positive-strand progen ...	1992	1731107
unique nucleotide differences in the conserved 3' termini of brome mosaic virus rnas are maintained through their optimization of genome replication.	to explore the functionality and conservation of specific base differences in the 3' 200 nucleotides of brome mosaic virus (bmv) rna-1 (1t) and rna-2 (2t) with respect to the 3' end of rna-3 (3t), all possible permutations were used to exchange these regions among the genomic rnas. when all rnas bore the 1t promoter, total rna accumulation was only 15% of wild type; when the 2t or 3t promoter was present on all three rnas total rna accumulation was reduced to 30 or 35% of wild type. two major pr ...	1992	1736528
expression of brome mosaic virus-encoded replicase genes in transgenic tobacco plants.	we introduced replicase genes of brome mosaic virus (bmv) to nicotiana tabacum cv. petit habana (sr1) using two different types of transformation vectors containing cdnas of bmv rna 1 and rna 2. one type (v type) contains cdna from which complete viral rnas are transcribed. these rnas can function as templates for viral replicase. the other type (m type) contains cdna from which viral rnas without their 3' non-coding regions are transcribed; these rnas can only function as mrna. viral replicase ...	1992	1730938
nucleotide sequence responsible for the synthesis of a truncated coat protein of brome mosaic virus strain atcc66.	the atcc66 strain of brome mosaic virus (bmv) (propagated at kyoto university) contained two types of coat protein in its virion whereas the russian strain of bmv has been known to contain a single coat protein; both strains have two initiation codons for coat protein in the same reading frame at the 5'-proximal end of the gene in rna 4. comparative studies on the nucleotide sequences of the atcc66 and russian strains of bmv demonstrated that in the atcc66 strain, two adjacent adenine residues w ...	1992	1402800
brome mosaic virus rna replication proteins 1a and 2a from a complex in vitro.	brome mosaic virus (bmv) is a positive-strand rna virus that encodes two rna replication proteins, the helicaselike 1a and the polymeraselike 2a. 1a and 2a share extensive sequence similarities with proteins encoded by many other members of the alphaviruslike superfamily. while further purifying enzymatically active rna-dependent rna polymerase from plants infected by bmv, we observed that 1a, 2a, and the polymerase activity all cofractionated through multiple independent purification steps. mor ...	1992	1404594
identification of the domains required for direct interaction of the helicase-like and polymerase-like rna replication proteins of brome mosaic virus.	brome mosaic virus is a positive-strand rna virus whose rna replication requires viral protein 1a, which has putative helicase and capping functions, and 2a, which has putative polymerase function. since domains of related sequence are conserved in a wide range of plus-strand rna viruses, analysis of 1a and 2a function should have applicability to many other viruses. we have recently demonstrated that 1a and 2a form a complex in vivo and in vitro. using immune coprecipitation and mutant polypept ...	1992	1433519
the nucleotide sequence of rna-1 of raspberry bushy dwarf virus.	raspberry bushy dwarf virus (rbdv) has isometric, 33 nm diameter particles and a bipartite rna genome. sequencing of the larger component (rna-1) showed that it consists of 5449 nucleotides and contains one large open reading frame encoding a putative translation product with a calculated m(r) of 190,000. comparisons of this polypeptide with non-structural proteins of other plant viruses revealed significant homologies with those of alfalfa mosaic virus (almv), brome mosaic virus (bmv), cucumber ...	1992	1469359