Publications

decline of specific infectivity of cowpea chlorotic mottle virus in vivo.		1965	14277092
properties of cowpea chlorotic mottle virus, its protein and nucleic acid.		1968	5640818
the significance of the multicomponent nature of cowpea chlorotic mottle virus rna.		1971	5166485
limited hydrolysis of cowpea chlorotic mottle virus by trypsin and chymotrypsin.		1971	5543278
cowpea chlorotic mottle virus local lesion area and infectivity increased by 2-thiouracil.		1971	5543264
partial sequence of the n-terminal portion of the protein of cowpea chlorotic mottle virus.		1972	5017148
enhancement of cowpea chlorotic mottle virus biosynthesis and in vivo infectivity by 2-thiouracil.		1972	5058332
inhibition of acquired resistance in cowpea chlorotic mottle virus-infected hypersensitive soybean by 2-thiouracil.		1973	4736597
structure and infectivity of picornaviral rna encapsidated by cowpea chlorotic mottle virus protein.	poliovirus and mengo virus rna were shown to associate efficiently with cowpea chlorotic mottle virus protein to form pseudovirions. the sedimentation coefficient for the pseudovirions was similar to that of poliovirus, and electron microscope observations showed the mengo pseudovirions to be similar in size to mengo virus. such pseudovirions were infectious and were more resistant to ribonuclease than viral rna; however, under our assay conditions, their infectivity was about equal to that of v ...	1973	4128376
the infection of tobacco protoplasts with cowpea chlorotic mottle virus and its rna.		1973	4584931
the mechanism of infection of plant protoplasts by viruses.	the process of virus infection of protoplasts isolated from tobacco leaves has been examined by means of electron microscopy. immediately after inoculation, virus particles appear at two types of site: trapped in complex surface lesions of the plasmalemma, or in peripheral cytoplasmic vesicles. the complex lesions are only visible after treatment of the protoplasts with inocula containing poly-l-ornithine. with infection by tobacco mosaic virus and cowpea chlorotic mottle virus, which require po ...	1973	24468812
minor protein components in cowpea chlorotic mottle virus and satellite of tobacco necrosis virus.		1974	4414688
structural changes accompanying infection of tobacco protoplasts with two spherical viruses.	ultrastructural changes occurring in isolated tobacco leaf protoplasts following infection with cowpea chlorotic mottle virus and bromegrass mosaic virus variant 5, have been examined. only the endoplasmic reticulum/nuclear membrane complex has shown a consistent series of changes in structure and distribution. both viruses induce proliferation of the endoplasmic reticulum and its modification. the nuclear membrane gives rise to small cytoplasmic vacuoles probably containing nucleic acid by a pr ...	1974	24458326
the conformation of the rna in cowpea chlorotic mottle virus: dye-binding studies.	the binding of the dye acridine orange to cowpea chlorotic mottle virus (ccmv) and its purified rna has been studied to obtain the number of dye-binding sites as a function of ph and, through further analysis, to estimate the degree of rna secondary structure in situ. acridine organe does not bind to ccmv protein and so the dye binding directly reflects the accessibility and structure of the rna. the number of dye molecules per nucleotide which can be bound by native virus (ph 4.5, i = 0.1 buffe ...	1975	237760
a negative staining-carbon film technique for studying viruses in the electron microscope. iii. the formation of two-dimensional and three-dimensional crystalline arrays of cowpea chlorotic mottle virus.		1975	54440
a mutant of cowpea chlorotic mottle virus with a perturbed assembly mechanism.		1976	12609
assembly of a spherical plant virus.	the conditions previously reported as necessary for the reassembly of spherical viruses have been distinctly unphysiological and such reassembly cannot be related directly to the in vivo reaction. mild conditions for the in vitro reassembly of cowpea chlorotic mottle virus (ccmv) from its isolated components have now been described (adolph & butler 1975) and the reassembled virus characterized. this reassembly involved the co-aggregation of the rna and protein around neutrality and at ionic stre ...	1976	13422
synchronization of cowpea chlorotic mottle virus replication in cowpea leaves.	a technique that 'systemically inoculates' cowpea leaves with cowpea chlorotic mottle virus (ccmv) is described. the upper leaves of cowpea plants are maintained at 10 degrees and allowed to become infected with inoculum from lower leaves maintained at 32 degrees; when the whole plant is shifted to 25 degrees, synchronous virus replication starts in the upper leaves. following the shift to 25 degrees, no infectivity could be detected during the first 6 h, after which the infectivity increased ex ...	1976	1010715
differential effect of 2-thiouracil on synthesis of two plant viruses in the same host.	in cowpea leaves singly or doubly infected with cowpea chlorotic mottle virus (ccmv) and/or southern bean mosaic virus (sbmv), treatment with 2-thiouracil increased the accumulation of ccmv particles and strongly decreased the accumulation of sbmv particles. thiouracil prevented the usual inhibition of synthesis of ccmv particles at about 6 days after inoculation, and 2-3 times as many ccmv particles accumulated as in water-treated plants. a single treatment of thiouracil 48 h before, at the tim ...	1977	870449
conformational states of cowpea chlorotic mottle virus ribonucleic acid components.	the conditions determining conformational changes in the four ribonucleic acid components of cowpea chlorotic mottle virus have been studied. all four components have at least two electrophoretically separable conformers, the occurrence of which can be regulated by both monovalent and polyvalent cations. this phenomenon also occurs, in a much less striking way, in the ribonucleic acids of the two other members of the bromovirus group, brome mosaic virus and broad bean mottle virus. although spec ...	1978	643624
isolation and mapping of replication-deficient, temperature-sensitive mutants of cowpea chlorotic mottle virus.		1978	716222
capsid fine structure of cowpea chlorotic mottle virus: from a computer analysis of negatively stained virus arrays.		1978	702634
characterization of rna-dependent rna polymerases in uninfected and cowpea chlorotic mottle virus-infected cowpea leaves: selective removal of host rna polymerase from membranes containing ccmv rna replicase.		1978	27898
time-course of cowpea chlorotic mottle virus rna replication.	in a synchronous infection of cowpea chlorotic mottle virus in cowpea leaves, the three largest viral rna components were synthesized throughout the infection at relatively constant ratios of two molecules of component 3 to one each of components 1 and 2. component 4 (the coat protein message) was produced minimally during the initial stages of the infection, and as the infection progressed the proportion of component 4 continuously increased. the replicative forms of components 1, 2, and 3 were ...	1978	618830
intrinsic fluorescence of cowpea-chlorotic-mottle-virus protein.		1979	37073
effect of cordycepin triphosphate on in vitro rna synthesis by plant viral replicases.	in vitro rna synthesis by tobacco mosaic virus and cowpea chlorotic mottle virus replicase were inhibited by cordycepin triphosphate. inhibition could be overcome with higher concentrations of atp in assay mixtures but not with utp. products synthesized in vitro by tobacco mosaic virus rna replicase in the presence of inhibitor revealed replicative form but not replicative intermediate rnas. these results suggest that cordycepin triphosphate competes specifically with atp and results in prematur ...	1979	16789174
double infection of tobacco protoplasts with brome mosaic virus and cowpea chlorotic mottle virus.	mixed infections of tobacco protoplasts with cowpea chlorotic mottle virus (ccmv) and brome mosaic virus (bmv) have been studied. fluorescent antibody staining showed that capsids of both viruses were made in doubly infected protoplasts but only infectious bmv could be recovered, i.e., bmv dominated in mixed infections and prevented synthesis of infectious ccmv. healthy protoplasts could be infected after several hours in culture but the susceptibility to infection decreased with time in culture ...	1980	18631680
the rnas of bromoviruses: 3'-terminal sequences of the four brome mosaic virus rnas and comparison with cowpea chlorotic mottle virus rna 4.		1980	7389920
fluorescence of cowpea-chlorotic-mottle virus modified with pyridoxal 5'-phosphate.	cowpea chlorotic mottle virus (ccmv), which is stable at ph 5.0, has been modified at this ph with 0.5--0.7 pyridoxal 5'-phosphate molecules per protein subunit. the fluorescence properties of the labelled ccmv protein in different aggregation states of the virus provide information about the labelled part of the protein and the changes induced in its environment, when the nucleo-protein particles are swollen or dissociated. fluorescence excitation and emission spectra indicate the presence of r ...	1980	6769672
the amino acid sequences of the tryptic peptides of cowpea chlorotic mottle virus protein.	the amino acid sequences of the major tryptic peptides from the coat protein of wild type cowpea chlorotic mottle virus are presented. the sequences have been determined by a combination of enzyme hydrolysis, mass spectrometry and edman degradation, and the relative usefulness of mass spectrometry in this peptide sequence determination is discussed.	1980	7000195
electron-paramagnetic-resonance spectroscopy of spin-labelled cowpea-chlorotic-mottle virus.	cowpea chlorotic mottle virus has been labelled with a maleimide spin label when the nucleoprotein particles were in the swollen state. after the spin-labelling reaction, the virus was dialyzed to bring the nucleoprotein particles into different conformational states. the mobility of the labelled part of the protein was monitored by electron paramagnetic resonance (epr) spectroscopy and by the saturation-transfer epr technique. the latter technique especially showed sensitivity to conditions tha ...	1981	6260487
effect of temperature-sensitive, replication-defective mutations on rna synthesis of cowpea chlorotic mottle virus.	the rna synthesis of replication-deficient, temperature-sensitive mutants of cowpea chlorotic mottle virus (ccmv) with mutations on either rna 1 or rna 3 was examined in temperature shift experiments. viral rna synthesis by the mutants at 25 degrees was similar to that of wild-type ccmv, but upon shift to 35 degrees , synthesis of mutant virus rnas declined over a 16-hr period in contrast to continued synthesis by wild-type ccmv. continued rna synthesis, though at a reduced level, by the mutants ...	1981	18635107
phosphorescence and optical detection of magnetic resonance of cowpea chlorotic mottle virus.	phosphorescence spectra of the tryptophan residues in cowpea chlorotic mottle virus were recorded at 77 k and the influence of the quaternary structure on the emission characteristics was investigated. the position of the phosphorescence maxima appeared to be invariant under changes in the aggregation state of the virus particle. in contrast to the results of fluorescence experiments, the phosphorescence probably originates from tryptophan residues, buried in the hydrophobic interior of the viru ...	1981	7236708
crystallization of cowpea chlorotic mottle virus.		1981	7277496
the primary structure of cowpea chlorotic mottle virus coat protein.	the amino acid sequence of the coat protein of wild-type cowpea chlorotic mottle virus has been nearly completely determined by direct methods. the sites of amino acid replacements were identified in the coat proteins of an oxidation-sensitive mutant, a temperature-sensitive mutant, and a salt-stable mutant. the replacements are a cysteinyl residue for the arginyl residue at position 25 in the oxidation-sensitive mutant, glutamic acid and alanine, respectively, for lysine and valine at positions ...	1982	18635150
complete nucleotide sequences of the coat protein messenger rnas of brome mosaic virus and cowpea chlorotic mottle virus.	the nucleotide sequences of the subgenomic coat protein messengers (rna4's) of two related bromoviruses, brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv), have been determined by direct rna and cdna sequencing without cloning. bmv rna4 is 876 b long including a 5' noncoding region of nine nucleotides and a 3' noncoding region of 300 nucleotides. ccmv rna 4 is 824 b long, including a 5' noncoding region of 10 nucleotides and a 3' noncoding region of 244 nucleotides. the encoded c ...	1982	6895941
open reading frame in the minus strand of two plus type rna viruses.	: inspection of the nucleotide sequences of the rnas complementary to the coat protein mrnas from two plant viruses with a tripartite genome: alfalfa mosaic virus and brome mosaic virus, showed the presence of open reading frames for 138 and 118 amino acids, respectively. a third virus (cowpea chlorotic mottle virus) from the same family (1) does not show this phenomenon. this suggests that if a protein is coded for by the open reading frames it may be not essential for virus multiplication. alt ...	1982	24317896
infection of cowpea mesophyll protoplasts with cowpea chlorotic mottle virus (ccmv) rna encapsulated in large liposomes.	it has been demonstrated that cowpea chlorotic mottle virus rna encapsulated in phosphatidyl serine/cholesterol reverse evaporation vesicles (rev) could infect cowpea mesophyll protoplasts under conditions known to enhance liposome-protoplast interactions. positively charged phosphatidylcholine/stearylamine multilamellar liposomes did not deliver functional ccmv rna despite their very high nucleic acid trapping capacity and their high affinity for protoplasts.	1983	24257855
rna-protein interactions and secondary structures of cowpea chlorotic mottle virus for in vitro assembly.	laser raman spectroscopy of the cowpea chlorotic mottle virus (ccmv) in native (ph 5.0) and partially swollen (ph 7.5) states reveals the presence of small percentages of protonated adenine (less than 15%) and cytosine (less than 7%) bases in the encapsidated rna molecule of the native virion. the protonated bases are titrated with ph-induced swelling of the virus. titration of putative cooh groups of aspartic and glutamic side chains of the virion subunit cannot be detected over the same ph ran ...	1984	6487602
specificity of the actinomycin-d-sensitive function of some rna plant viruses.	the actinomycin-d(amd)-sensitive step of replication of three plant viruses - cowpea chlorotic mottle virus (ccmv), cowpea mosaic virus, and the cowpea strain of tobacco mosaic virus - in cowpea was specific for each virus. different combinations of the viruses were examined in which leaves were inoculated with one virus and incubated for 48 h until multiplication was almost resistant to amd. at that time, the same leaves were inoculated with a different virus and the ability of amd to inhibit m ...	1984	6735660
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
the semipermeability of simple spherical virus capsids.	hydrogen-ion titration curves are reported for tomato bushy stunt virus, two strains of cowpea chlorotic mottle virus, and turnip crinkle virus, with particular attention to the hysteresis loops associated with the swelling and contraction of virions. there appears to be an archetypal shape of hysteresis loops, which is shared by viruses in several groups, suggestive of many intermediate states in the swelling of any one particle. in contrast, eggplant mosaic virus behaves as if its protein caps ...	1984	18639804
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
role of the n-terminal part of the coat protein in the assembly of cowpea chlorotic mottle virus. a 500 mhz proton nuclear magnetic resonance study and structural calculations.	the interaction of the oligonucleotides (ap)8a and (a-t)5 with empty capsids of the coat protein of cowpea chlorotic mottle virus (ccmv) has been studied with 500 mhz 1h nuclear magnetic resonance. it is found that these oligonucleotides specifically bind to the arginine and lysine residues of the n-terminal arm of the protein. upon this binding, immobilization of part of the n-terminal arm occurs. in addition, secondary structure predictions and energy calculations have been performed on the n- ...	1986	3820293
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
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
binding of cowpea chlorotic mottle virus to cowpea protoplasts and relation of binding to virus entry and infection.	cowpea chlorotic mottle virus (ccmv) and cowpea protoplasts were used to study initial interactions between virus and protoplast. protoplasts and virus were incubated under varying conditions of temperature, ph, ionic strength, and the presence of added compounds. both the amount of 35s-labeled virus bound to protoplasts and the percentage of infected cells were determined. at 0 and 25 degrees the amount of virus associated with protoplasts increased with the amount of virus added. with inoculum ...	1988	3363871
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
virus-ribosome complexes from cell-free translation systems supplemented with cowpea chlorotic mottle virus particles.	when particles of cowpea chlorotic mottle virus (ccmv) were added to cell-free extracts from wheat germ, the encapsidated viral genome was translated into polypeptides similar to the translation products specified by unencapsidated viral rna (as shown before by m.j. brisco, r. hull, and t.m.a. wilson, 1986, virology 148, 210-217). the rate of protein synthesis observed upon addition of virus particles was much slower than that of extracted rna and the quantity of protein formed was only 10% of t ...	1989	2909987
logistic and poisson models for infection by multicomponent plant viruses.	a model for the relationship between virus concentration and infectivity of multicomponent plant viruses is based on a combination of logistic and poisson equations. two separate equations are derived from the poisson distribution assuming, (i) that infections occur only when a set of components containing the complete multicomponent genome is established at an infection site, but that any excess of components present does not reduce the probability of infection (no interference postulate); and ...	1989	2613853
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
regeneration of a functional rna virus genome by recombination between deletion mutants and requirement for cowpea chlorotic mottle virus 3a and coat genes for systemic infection.	rnas 1 and 2 of the tripartite cowpea chlorotic mottle virus (ccmv) genome are sufficient for rna replication in protoplasts, whereas systemic infection of cowpea plants additionally requires rna3, which encodes the 3a noncapsid protein and coat protein. by using biologically active ccmv cdna clones, we find that deletions in either rna3 gene block systemic infection. thus, though some plant rna viruses are able to spread systemically without encapsidation, both the coat and 3a genes are require ...	1990	2308940
the nucleotide sequence and genome organization of the rna-1 segment in two bromoviruses: broad bean mottle virus and cowpea chlorotic mottle virus.	the complete nucleotide sequences of the rna-1 segments in broad bean mottle virus (bbmv) and cowpea chlorotic mottle virus (ccmv) were determined. bbmv rna-1 consists of 3158 nucleotides and ccmv rna-1 has 3171 nucleotides. both bbmv and ccmv rna-1 are capped at the 5' end but, unlike in other tricornaviruses, bbmv rna-1 initiates with an a residue. both bbmv and ccmv rna-1 are monocistronic encoding for highly homologous 1a proteins of 966 and 958 amino acids, respectively. the highest homolog ...	1991	1962437
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
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
solution conformation of a peptide fragment representing a proposed rna-binding site of a viral coat protein studied by two-dimensional nmr.	the first 25 amino acids of the coat protein of cowpea chlorotic mottle virus are essential for binding the encapsidated rna. although an alpha-helical conformation has been predicted for this highly positively charged n-terminal region [argos, p. (1981) virology 110, 55-62; vriend, g., verduin, b. j. m., & hemminga, m. a. (1986) j. mol. biol. 191, 453-460], no experimental evidence for this conformation has been presented so far. in this study, two-dimensional proton nmr experiments were perfor ...	1991	1904274
conformational studies on a peptide fragment representing the rna-binding n-terminus of a viral coat protein using circular dichroism and nmr spectroscopy.	conformational studies were performed on a synthetic pentacosapeptide representing the rna-binding n-terminal region of the coat protein of cowpea chlorotic mottle virus. the effects of ionic strength, addition of (oligo)phosphates and temperature on the conformation of this highly positively charged peptide containing six arginines and three lysines were studied. cd experiments show that the peptide has 15-18% alpha-helical conformation and about 80% random-coil conformation in the absence of i ...	1991	1935944
conformation and mobility of the rna-binding n-terminal part of the intact coat protein of cowpea chlorotic mottle virus. a two-dimensional proton nuclear magnetic resonance study.	two-dimensional proton nuclear magnetic resonance (n.m.r.) experiments were performed on the coat protein of cowpea chlorotic mottle virus (molecular mass: 20.2 kda) present as dimer (ph 7.5) or as capsid consisting of 180 protein monomers (ph 5.0). the spectra of both dimers and capsids showed resonances originating from the flexible n-terminal region of the protein. the complete resonance assignment of a synthetic pentacosapeptide representing this n terminus made it possible to interpret the ...	1991	1908015
conformation of a pentacosapeptide representing the rna-binding n-terminus of cowpea chlorotic mottle virus coat protein in the presence of oligophosphates: a two-dimensional proton nuclear magnetic resonance and distance geometry study.	conformational studies were performed on a synthetic pentacosapeptide representing the rna-binding n-terminal region of the coat protein of cowpea chlorotic mottle virus. two-dimensional proton nmr experiments were performed on the highly positively charged peptide containing six arginines and three lysines in the presence of an excess of monophosphates, tetra(poly)phosphates, or octadeca(poly)phosphates mimicking the phosphates of the rna. the results show that the peptide alternates between va ...	1992	1390704
a hybrid plant rna virus made by transferring the noncapsid movement protein from a rod-shaped to an icosahedral virus is competent for systemic infection.	for many plant rna viruses, multiple viral gene products, including noncapsid movement proteins and capsid proteins, contribute to the spread of infection within plants. the extent to which these factors interact to support infection spread is not known, but, for movement protein mutants of certain viruses, the inability of coinoculated "helper" viruses to complement defective movement has suggested a possible requirement for coadaptation between noncapsid movement proteins and other virus facto ...	1992	1495969
the nucleotide sequence and genome organization of the rna2 and rna3 segments in broad bean mottle virus.	complete nucleotide sequences of broad bean mottle virus (bbmv) genomic rnas 2 and 3 were determined. they consist of 2811 and 2293 nucleotides, respectively. both rnas are caped and, unlike in other tricornaviruses, both initiate with an a residue. bbmv rna2 is monocistronic and encodes an 815 amino acid 2a protein, whereas rna3 is dicistronic, encoding for a 295 amino acid 3a protein and for the 190 amino acid coat protein. a central, 423 amino acid 2a protein core region is highly homologous ...	1992	1546462
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
substantial portions of the 5' and intercistronic noncoding regions of cowpea chlorotic mottle virus rna3 are dispensable for systemic infection but influence viral competitiveness and infection pathology.	cowpea chlorotic mottle virus (ccmv) has a tripartite, positive strand rna genome. genomic rna3 (2.2 kb) encodes the 3a nonstructural protein and the coat protein, which are dispensable for viral rna synthesis in protoplasts, but required for systemic infection of whole plants. in protoplasts, portions of the 5' and intercistronic noncoding regions of ccmv rna3 are also dispensable for rna3 replication and for transcription of the subgenomic coat protein mrna. to determine whether these noncodin ...	1992	1736532
bromovirus rna replication and transcription require compatibility between the polymerase- and helicase-like viral rna synthesis proteins.	the positive-strand rna bromoviruses encode two nonstructural proteins, 1a and 2a, involved in rna-dependent rna replication. these proteins have extensive sequence similarities with methyltransferase, helicase, and polymerase proteins of other plant and animal viruses. 1a and 2a can also form a complex in vitro. to explore whether 1a-2a interaction is required for rna replication in vivo, we reassorted the 1a and 2a genes from two different bromoviruses, brome mosaic virus (bmv) and cowpea chlo ...	1993	8230440
in vitro destabilization of plant viruses and cdna synthesis.	dna copies of a wide range of rna viruses can be made by the direct addition of appropriately treated, purified virus particles to a reverse transcription reaction. therefore, many problems associated with rna isolation can be circumvented. virus particles can be sufficiently destabilized by adjustments of salt content, buffer, ph or by the use of physical force supplied by a freeze/thaw cycle so that rna in sufficient quantity and physical condition is available for the synthesis of in some cas ...	1993	8263116
bromovirus movement protein genes play a crucial role in host specificity.	monocot-adapted brome mosaic virus (bmv) and dicot-adapted cowpea chlorotic mottle virus (ccmv) are closely related bromoviruses with tripartite rna genomes. although rnas 1 and 2 together are sufficient for rna replication in protoplasts, systemic infection also requires rna3, which encodes the coat protein and the nonstructural 3a movement protein. we have previously shown with bromoviral reassortants that host specificity determinants in both viruses are encoded by rna3 as well as by rna1 and ...	1993	7682628
preliminary x-ray data analysis of crystalline cowpea chlorotic mottle virus.	crystals of cowpea chlorotic mottle virus (ccmv) that diffract x-rays to 3.1 a resolution were grown in a succinate-peg solution buffered at ph 3.3. the crystals are in space group p2(1)2(1)2(1) with unit cell dimensions of a = 381.26 a, b = 381.26 a, and c = 408.59 a. four particles occupy the unit cell, placing a single virion in the crystallographic asymmetric unit. diffraction intensities measured from 196 films collected at the cornell high energy synchrotron source accounted for 55% of the ...	1993	8438568
conformational changes in oligo-nucleotides upon binding to a peptide representing the n-terminal region of a viral coat protein. an optical spectroscopy study.	conformational changes of the oligonucleotides r(a)12, d(gc)5, and d(at)5 upon binding to a pentacosapeptide representing the rna-binding n-terminus of the coat protein of cowpea chlorotic mottle virus (ccmv) were studied by using absorption and circular dichroism spectroscopy. the peptide destabilizes the single-stranded structure of r(a)12 at ph 7.2, but disrupts the double-stranded structure of r(a)12 at ph 5.0. however, at ph 4.0, the peptide is not able to disrupt this double-stranded struc ...	1993	8439547
recombination between viral rna and transgenic plant transcripts.	transformed plants expressing the 3' two-thirds of the cowpea chlorotic mottle virus (ccmv) capsid gene were inoculated with a ccmv deletion mutant lacking the 3' one-third of the capsid gene. although the deletion inoculum replicates in inoculated cells, systemic infections occur only if recombination restores a functional capsid gene. four of 125 inoculated transgenic plants, representing three different transgenic lines, became systemically infected. analysis of viral rna confirmed that rna r ...	1994	8128222
the nucleotide sequence of citrus leaf rugose ilarvirus rna-2.	the nucleotide sequence of citrus leaf rugose ilarvirus (cilrv) rna-2 consists of 2990 nucleotides and contains one open reading frame (orf) which encodes a deduced translation product of 832 amino acids with a calculated m(r) of 95,501 (95k). the 5' terminus of the rna has a m7gppp cap. both the nucleotide sequence of cilrv rna-2 and its translated polypeptide share homologies with the nucleotide sequence and translated polypeptide, respectively, of rna-2 of alfalfa mosaic virus (almv). the hom ...	1994	7931176
in vitro assembly of cowpea chlorotic mottle virus from coat protein expressed in escherichia coli and in vitro-transcribed viral cdna.	the small spherical plant virus, cowpea chlorotic mottle virus (ccmv), provides an ideal system to examine spherical virus assembly. we have modified the ccmv in vitro assembly system to produce virions from coat protein expressed in escherichia coli and viral rna transcribed in vitro from full-length cdnas. examination of the in vitro-assembled particles with cryoelectron microscopy and image reconstruction techniques demonstrates that the particles are indistinguishable from plant purified par ...	1995	7886952
structures of the native and swollen forms of cowpea chlorotic mottle virus determined by x-ray crystallography and cryo-electron microscopy.	rna-protein interactions stabilize many viruses and also the nucleoprotein cores of enveloped animal viruses (e.g. retroviruses). the nucleoprotein particles are frequently pleomorphic and generally unstable due to the lack of strong protein-protein interactions in their capsids. principles governing their structures are unknown because crystals of such nucleoprotein particles that diffract to high resolution have not previously been produced. cowpea chlorotic mottle virions (ccmv) are typical o ...	1995	7743132
foreign complementary sequences facilitate genetic rna recombination in brome mosaic virus.	we have demonstrated that local antisense sequences can mediate genetic recombination within the 3' noncoding region among brome mosaic virus (bmv) rnas (p. nagy and j. j. bujarski, 1993, proc. natl. acad. sci. usa 90, 6390-6394). here we show that foreign complementary inserts can direct crossovers between bmv rna3 components within an internal region. a 170-nt polynucleotide derived from the cowpea chlorotic mottle virus (ccmv) rna3 was inserted just upstream of the initiation codon of the bmv ...	1995	11831722
the polymerase-like core of brome mosaic virus 2a protein, lacking a region interacting with viral 1a protein in vitro, maintains activity and 1a selectivity in rna replication.	brome mosaic virus (bmv), a member of the alphavirus-like super-family of positive-strand rna viruses, encodes two proteins required for viral rna replication: 1a and 2a. 1a contains m7g methyltransferase- and helicase-like domains, while 2a contains a polymerase (pol)-like core flanked by n- and c-terminal extensions. genetic studies show that bmv rna replication requires 1a-2a compatibility implying direct or indirect 1a-2a interaction in vivo. in vitro, la interacts with the n-terminal 125-am ...	1996	8676500
analysis of a salt stable mutant of cowpea chlorotic mottle virus.	an understanding of virion assembly and disassembly requires a detailed understanding of the protein-protein and protein-nucleic acid interactions which stabilize the virion. we have characterized a mutant of cowpea chlorotic mottle virus (ccmv) that is altered in virion stability. the mutant virions resist disassembly in 1.0 m nacl, ph 7.5, whereas the wild-type virions completely disassociate into rna and capsid protein components. sequence analysis of the mutant coat protein gene identified a ...	1996	8806492
a single codon change in a conserved motif of a bromovirus movement protein gene confers compatibility with a new host.	brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) are closely related bromoviruses with tripartite rna genomes, but distinct host ranges: bmv systemically infects the monocot barley, while ccmv systemically infects the dicot cowpea. we have previously shown that in approximately 10% of inoculated cowpea plants, a ccmv hybrid [ccmv(b3a)] with the 3a cell-to-cell movement protein gene replaced by that of cowpea-nonadapted bmv directs systemic infections, which are caused by seconda ...	1996	8806564
molecular modeling of the rna binding n-terminal part of cowpea chlorotic mottle virus coat protein in solution with phosphate ions.	the rna-binding n-terminal arm of the coat protein of cowpea chlorotic mottle virus has been studied with five molecular dynamics simulations of 2.0 ns each. this 25-residue peptide (pep25) is highly charged: it contains six arg and three lys residues. an alpha-helical fraction of the sequence is stabilized in vitro by salts. the interaction of monophosphate (pi) ions with pep25 was studied, and it was found that only two pi ions are bound to pep25 on average, but water-mediated interactions bet ...	1996	8968565
deletions in the 3' untranslated region of cowpea chlorotic mottle virus transgene reduce recovery of recombinant viruses in transgenic plants.	the 3' untranslated region (utr) adjacent to the capsid gene is frequently included with the transgene in the construction of capsid protein mediated virus resistant transgenic plants. since ribonucleotide sequences within the 3' utr are involved in the initiation of viral replication, the presence of this sequence may encourage the participation of the transgene in rna recombination. experiments were designed to explore the involvement of the 3' utr of cowpea chlorotic mottle virus (ccmv) in rn ...	1996	8918552
virion swelling is not required for cotranslational disassembly of cowpea chlorotic mottle virus in vitro.	the mechanism by which virions of cowpea chlorotic mottle virus (ccmv) disassemble and allow for translation of the virion rna is not well understood. previous models have suggested that virion swelling is required to expose the virion rna for translation in a process referred to as cotranslational disassembly (m. brisco, r. hull, and t. m. a. wilson, virology 148:210-217, 1986; j. w. roenhorst, j. w. m. van lent, and b. j. m. verduin, virology 164:91-98, 1988; j. w. roenhorst, j. m. verduin, an ...	1997	9151817
characterization of a disassembly deficient mutant of cowpea chlorotic mottle virus.	an understanding of virus disassembly requires a detailed understanding of the protein-protein and protein-nucleic acid interactions which stabilize the virion. we have characterized a mutant of cowpea chlorotic mottle virus [cpr26c (coat protein r26c)] that displays increased virion stability and is abnormal in virion disassembly when purified under nonreducing conditions. reduced virions are infectious, whereas nonreduced virions are noninfectious. the cpr26c mutant virions purified under nonr ...	1997	9007078
quasi-equivalent viruses: a paradigm for protein assemblies.	the structure and assembly of icosahedral virus capsids composed of one or more gene products and displaying quasi-equivalent subunit associations are discussed at three levels. the principles of quasi-equivalence and the related geodesic dome formation are first discussed conceptually and the geometric basis for their construction from two-dimensional assembly units is reviewed. the consequences for such an assembly when three-dimensional protein subunits are the associating components are then ...	1997	9223631
structure-based rationale for the rescue of systemic movement of brome mosaic virus by spontaneous second-site mutations in the coat protein gene.	we describe spontaneous second-site reversions within the coat protein open reading frame that rescue the systemic-spread phenotype and increase virion stability of a mutant of brome mosaic virus. based on the crystal structure of the related cowpea chlorotic mottle virus, we show that the modified residues are spatially clustered to affect the formation of hexamers and pentamers and therefore virion stability.	1997	9032390
the structure of cucumber mosaic virus: cryoelectron microscopy, x-ray crystallography, and sequence analysis.	the three-dimensional structure of cucumber mosaic virus (cmv) was analyzed at 23 a resolution by cryoelectron microscopy and image reconstruction, demonstrating structural similarity to cowpea chlorotic mottle virus (ccmv), another member of the bromoviridae family. the cmv structure was determined at 8 a resolution by x-ray crystallography with phases determined by single isomorphous replacement and refined by fivefold noncrystallographic symmetry averaging. the x-ray structure agreed with the ...	1997	9185592
effects of coat protein mutations and reduced movement protein expression on infection spread by cowpea chlorotic mottle virus and its hybrid derivatives.	previously we have reported that the essential 3a movement gene of icosahedral cowpea chlorotic mottle virus (ccmv) can be functionally replaced by the 30-kda movement gene of rod-shaped sunn-hemp mosaic virus (shmv). because plant rna viruses differ in requiring or not requiring coat protein for systemic infection, we have now investigated whether systemic spread by this ccmv/shmv hybrid is dependent on its ccmv coat protein as well as its shmv movement protein. we find that either deletion or ...	1997	9185600
molecular studies on bromovirus capsid protein. iii. analysis of cell-to-cell movement competence of coat protein defective variants of cowpea chlorotic mottle virus.	to determine whether the role of coat protein (cp) in cell-to-cell movement of dicot-adapted cowpea chlorotic mottle bromovirus (ccmv) is distinct from that of monocot-adapted brome mosaic bromovirus (bmv), two reporter genes, beta-glucuronidase (gus) and enhanced green fluorescent protein (egfp), were substituted for the cp in a biologically active clone of ccmv rna3 (c3). primary leaves of nicotiana benthamiana, chenopodium quinoa, and cowpea were co-inoculated with wild-type (wt) ccmv rna 1 a ...	1997	9191853
analysis of the interaction of viral rna replication proteins by using the yeast two-hybrid assay.	the yeast two-hybrid system has been a useful tool in the genetic evaluation of protein-protein interactions. however, the biological relevance of these two-hybrid interactions to viral positive-strand rna replication has not been demonstrated. the brome mosaic virus (bmv) system has been characterized extensively both genetically and biochemically, providing numerous mutations in the bmv 1a helicase-like and 2a polymerase-like proteins. we have tested wild-type 1a and 18 insertion mutations of ...	1997	9311832
iris explorer software for radial-depth cueing reovirus particles and other macromolecular structures determined by cryoelectron microscopy and image reconstruction.	structures of biological macromolecules determined by transmission cryoelectron microscopy (cryo-tem) and three-dimensional image reconstruction are often displayed as surface-shaded representations with depth cueing along the viewed direction (z cueing). depth cueing to indicate distance from the center of virus particles (radial-depth cueing, or r cueing) has also been used. we have found that a style of r cueing in which color is applied in smooth or discontinuous gradients using the iris exp ...	1997	9361260
molecular studies on bromovirus capsid protein. iv. coat protein exchanges between brome mosaic and cowpea chlorotic mottle viruses exhibit neutral effects in heterologous hosts.	two members of the bromovirus group, brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv), selectively infect barley and cowpea, respectively, and also differ in their ability to systemically infect a common permissive host, chenopodium quinoa. ccmv is confined to inoculated leaves of c. quinoa, whereas bmv causes rapid systemic mottling. to examine whether host-specific determinants for systemic movement of bmv and ccmv in each of these hosts are localized in the coat protein (cp), ...	1997	9400617
characterization of the nucleic acid binding properties of tomato spotted wilt virus nucleocapsid protein.	tomato spotted wilt tospovirus (tswv) is the type member of the plant-infecting viruses of the genus tospovirus in the family bunyaviridae. the three tswv rnas are encapsidated with nucleocapsid (n) protein to form ribonucleoprotein (rnp) which serves as the template for viral transcription and replication. regions of the open reading frame coding for the n protein on the small (s) rna were subcloned into pet protein expression vectors and expressed in escherichia coli bl21 (de3) cells. full-len ...	1998	9705250
subgenomic rna promoters dictate the mode of recognition by bromoviral rna-dependent rna polymerases.	both the brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) rna-dependent rna polymerases (rdrps) were found to recognize the bmv core subgenomic promoter in the same manner, requiring specific functional groups at positions -17, -14, -13, and -11 relative to the subgenomic initiation site (+1). for ccmv subgenomic rna synthesis, both rdrps required the same nucleotides and four additional nucleotides at positions -20, -16, -15, and -10. the -20 nucleotide is partially responsible ...	1998	9875310
crystalline cowpea chlorotic mottle virus.		1998	21302
comparison of the native ccmv virion with in vitro assembled ccmv virions by cryoelectron microscopy and image reconstruction.	cryoelectron microscopy and three-dimensional image reconstruction analysis has been used to determine the structure of native and in vitro assembled cowpea chlorotic mottle virus (ccmv) virions and capsids to 25-a resolution. purified ccmv coat protein was used in conjunction with in vitro transcribed viral rnas to assemble rna 1 only, rna 2 only, rna 3/4 only, and empty (rna lacking) virions. the image reconstructions demonstrate that the in vitro assembled ccmv virions are morphologically ind ...	1998	9581792
effect of c-terminal deletions in the movement protein of cowpea chlorotic mottle virus on cell-to-cell and long-distance movement.	in order to elucidate the function of the c-terminal region of cowpea chlorotic mottle bromovirus (ccmv) movement protein (mp) in cell-to-cell movement, a set of deletions ranging from 10 to 80 amino acids (deltamp10, deltamp20, deltamp33, deltamp43, deltamp60 and deltamp80) was engineered into the mp gene encoded by the biologically active clone c3/deltacp-egfp, a variant of ccmv rna3 that contained wild-type (wt) mp and the enhanced green fluorescent protein (egfp) gene in place of the coat pr ...	1999	10374951
identification of a cell surface protein from crandell feline kidney cells that specifically binds aleutian mink disease parvovirus.	aleutian mink disease parvovirus (adv) is the etiological agent of aleutian disease of mink. the acute disease caused by adv consists of permissive infection of alveolar type ii cells that results in interstitial pneumonitis. the permissive infection is experimentally modeled in vitro by infecting crandell feline kidney (crfk) cells with a tissue culture-adapted isolate of adv, adv-g. adv-g vp2 empty virions expressed in a recombinant baculovirus system were analyzed for the ability to bind to t ...	1999	10196278
evolutionarily related sindbis-like plant viruses maintain different levels of population diversity in a common host.	the levels of population diversity of three related sindbis-like plant viruses, tobacco mosaic virus (tmv), cucumber mosaic virus (cmv), and cowpea chlorotic mottle virus (ccmv), in infections of a common host, nicotiana benthamiana, established from genetically identical viral rna were examined. despite probably having a common evolutionary ancestor, the three viruses maintained different levels of population diversity. cmv had the highest levels of diversity, tmv had an intermediate level of d ...	2000	10708428
the structure of cucumber mosaic virus and comparison to cowpea chlorotic mottle virus.	the structure of cucumber mosaic virus (cmv; strain fny) has been determined to a 3.2-a resolution using x-ray crystallography. despite the fact that cmv has only 19% capsid protein sequence identity (34% similarity) to cowpea chlorotic mottle virus (ccmv), the core structures of these two members of the bromoviridae family are highly homologous. as suggested by a previous low-resolution structural study, the 305-a diameter (maximum) of cmv is approximately 12 a larger than that of ccmv. in ccmv ...	2000	10906212
mechanism of capsid assembly for an icosahedral plant virus.	capsids of spherical viruses share a common architecture: an icosahedral arrangement of identical proteins. we suggest that there may be a limited number of common assembly mechanisms for such viruses. previous assembly mechanisms were proposed on the basis of virion structure but were not rigorously tested. here we apply a rigorous analysis of assembly to cowpea chlorotic mottle virus (ccmv), a typical, small, positive-strand rna virus. the atomic resolution structure of ccmv revealed an interl ...	2000	11080492
bromovirus movement protein conditions for the host specificity of virus movement through the vascular system and affects pathogenicity in cowpea.	previously, we reported that ccmv(b3a), a hybrid of bromovirus cowpea chlorotic mottle virus (ccmv) with the 3a cell-to-cell movement protein (mp) gene replaced by that of cowpea-nonadapted bromovirus brome mosaic virus (bmv), can form small infection foci in inoculated cowpea leaves, but that expansion of the foci stops between 1 and 2 days postinoculation. to determine whether the lack of systemic movement of ccmv(b3a) is due to restriction of local spread at specific leaf tissue interfaces, w ...	2000	11059486
effects of cowpea chlorotic mottle virus (soybean strain) on chemical composition of davis soybeans.		2000	5528923