Publications

serological relationships among members of the cowpea mosaic virus group.		1966	4380471
infectivity of a mixture of cowpea mosaic virus ribonucleoprotein components.		1967	4960987
purification and properties of the components of cowpea mosaic virus.		1967	6022691
electron microscopy of leaves infected with sowbane mosaic virus and other small polyhedral viruses.	leaves of chenopodium amaranticolor were infected with sowbane mosaic virus (smv), sectioned and examined by electron microscopy. leaves of brassica pekinensis and c. amaranticolor were infected with turnip yellow mosaic virus and cowpea mosaic virus, respectively, and similarly studied. with all three viruses it was difficult, in sections, to distinguish the small isometric virus particles from ribosomes though sometimes this was possible, especially when the viruses crystallized. pretreatment ...	1967	18614059
the relationship between the components of cowpea mosaic virus. i. two ribonucleoprotein particles necessary for the infectivity of cpmv.		1968	5640822
conversion of the electrophoretic forms of cowpea mosaic virus in vivo and in vitro.		1969	4979607
the isolation of ribonuclease-resistant rna induced by cowpea mosaic virus: evidence for two double-stranded rna components.		1969	5786160
the inheritance of top component formation in cowpea mosaic virus.		1969	5781861
the relationship between the components of cowpea mosaic virus. 3. location of genetic information for two biological functions in the middle component of cpmv.		1970	5422720
the relationship between the components of cowpea mosaic virus. ii. further characterization of the nucleoprotein components of cpmv.		1970	5422719
the significance of the coat protein in infection by the electrophoretic forms of cowpea mosaic virus.		1970	5422717
two proteins from cowpea mosaic virus.		1971	5137799
hydrogen ion effects on the thermal inactivation of cowpea mosaic virus.		1971	5002942
structure in cells of vigna unguiculata infected with cowpea mosaic virus.		1971	4108621
buoyant density changes of cowpea mosaic virus components at different ph values.		1971	5543838
genetic complementation between the two nucleoprotein components of cowpea mosaic virus.		1972	5053105
structure of the capsid of cowpea mosaic virus. the chemical subunit: molecular weight and number of subunits per particle.		1972	5039022
polyadenylate sequences in the ribonucleic acids of cowpea mosaic virus.		1973	4745624
characterization of the double-stranded rna isolated from cowpea mosaic virus-infected vigna leaves.		1973	4696555
the localization of virus-specific double-stranded rna of cowpea mosaic virus in subcellular fractions of infected vigna leaves.		1973	4576343
structure of isometric viruses containing nonidentical polypeptide chains.	the theory of caspar and klug (1962) for the structure of isometric viruses has been generalized to the case in which the identical repeating unit is composed of n nonidentical polypeptide chains. this modified theory accounts for the structure of picornaviruses, the lambda phage head, cowpea mosaic virus, and phix174, while at the same time conserving the principle of having identical subunits in identical environments. furthermore, the modified theory suggests amending the triangulation number ...	1974	4418754
in vitro replication of cowpea mosaic virus rna: i. isolation and properties of the membrane-bound replicase.	a fraction which contained the membrane-bound cowpea mosaic virus rna replicase was isolated from cowpea mosaic virus-infected cowpea leaves. the replicase activity appeared on day 1 after inoculation, then increased to reach a maximal on day 4. the increase in enzyme activity preceded the most-rapid virus multiplication. the membrane-bound replicase activity was almost completely insensitive to actinomycin d and dnase. the corresponding fraction from healthy leaves had no rna-dependent rna poly ...	1974	4431078
association of cowpea mosaic virus-induced double-stranded rna with a cytopathological structure in infected cells.		1974	4364824
insect vectors of cowpea mosaic virus in nigeria.		1974	4470367
a three-dimensional image reconstruction of cowpea mosaic virus.		1974	4131954
the ultrastructural appearance of cowpea mosaic virus in cowpea.		1975	47914
infection of cowpea mesophyll protoplasts with cowpea mosaic virus.		1975	237360
the pattern of amino acid incorporation into two cowpea mosaic virus proteins in the presence of ribosome-specific protein synthesis inhibitors.		1975	124497
the use of an abrasive in the isolation of cowpea leaf protoplasts which support the multiplication of cowpea mosaic virus.		1975	1114711
factors influencing the infection of cowpea protoplasts by cowpea mosaic virus rna.		1976	7877
electrophoretic mobility and enhanced infectivity of a mutant of cowpea mosaic virus.		1976	936474
genetic analysis of cowpea mosaic virus mutants by supplementation and reassortment tests.		1976	1258375
in vitro replication of cowpea mosaic virus rna. ii. solubilization of membrane-bound replicase and the partial purification of the solubilized enzyme.	a method for the solubilization of membrane-bound cowpea mosaic virus rna replicase has been developed by bypassing the use of detergents. solubilization has been achieved by washing the 31,000 x g-pellet containing the bound replicase with a mg2+-deficient buffer. this procedure had several advantages as compared to treatments with nonionic or ionic detergents: (i) the solubilized enzyme was stable at 4 c, (ii) more than 80% of the replicase could be solubilized without loss of total enzyme act ...	1976	1255853
proceedings: properties of the template-dependent cowpea mosaic virus replicase.		1976	1275384
an efficient mrna-dependent translation system from reticulocyte lysates.	a simple method is described for converting a standard rabbit reticulocyte cell-free extract (lysate) into an mrna-dependent protein synthesis system. the lysate is preincubated with cacl2 and micrococcal nuclease, and then excess ethyleneglycol-bis(2-aminoethylether)-n,n'-tetraacetic acid is added to chelate the ca2+ and inactivate the nuclease. lysates treated in this way have neglibible endogenous amino acid incorporation activity, but 75% of the activity of the original lysate can be recover ...	1976	823012
location of the gene specifying the smaller protein of the cowpea mosaic virus capsid.		1977	867824
translation of cowpea mosaic virus rna in a cell-free extract from wheat germ.		1977	862928
cowpea mosaic virus rnas have neither m7gpppn ... nor mono-, di- or triphosphates at their 5' ends.	32p-labeled cowpea mosaic virus (cpmv) rnas were analyzed for their 5' termini by three different fingerprinting standard procedures. these analyses showed unequivocally that cpmv rnas lack a structure like m7gpppn ... at their 5' termini. in addition, neither mono-, di- or triphosphorylated [(p)(p)pn ....] termini were found in the respective fingerprints. the inability to label the 5' termini treatment with gamma-32p-atp and polynucleotide kinase, either per se or after pretreatment with alkal ...	1977	872220
genetic and physiological characterization of a temperature-sensitive mutant of cowpea mosaic virus.		1977	835227
a protein linked to the 5' termini of both rna components of the cowpea mosaic virus genome.	evidence is presented for the presence of a protein covalently bound to the 5' termini of both m and b rna components of cpmv. the protein is found to be linked in both cases to the 5' phosphate of the dinucleotide pupap, derived by ribonuclease digestion of the rna. the intact protein is not required for infectivity or for in vitro translation of the rna in cell-free extracts.	1978	745988
characterization of the 3' termini of the rnas of cowpea mosaic virus.	a sequence of polyadenylic acid, homogeneous in composition but heterogeneous in length, was isolated from complete pancreatic rnase digests of both middle and bottom rnas of cowpea mosaic virus. the polyadenylic acid was 3'-terminal and occurred once per molecule. a fragment consisting of the polyadenylic acid and approximately the next 25 nucleotides could be isolated from complete t1 rnase digests of either rna. the region adjacent to the polyadenylic acid in both rnas was rich in pyrimidines ...	1978	16789170
complementation and pseudorecombination between ribonucleic acids from two natural isolates of cowpea mosaic virus (severe subgroup).		1978	77077
efficient reverse transcription of cowpea mosaic virus rnas.	conditions are described which give an efficient synthesis of dna copies of cowpea mosaic virus (cpmv) rnas, using avian myeloblastosis reverse transcriptase and oligo (dt) primers. maximum incorporation of damp into cdna is attained with 0.4 to 0.8 mm of each deoxynucleoside triphosphate, 12 mm mg++ and 60 mm k+ ion concentrations. high enzyme concentrations (up to 100 units/ml) were used. under these conditions over 1000 pmoles of damp were incorporated per reaction. the cdna:rna molar ratio ...	1978	85293
sequence homology adjacent to the 3' terminal poly(a) of cowpea mosaic virus rnas.	we have determined the sequence of 80 nucleotides adjacent to 3' poly(a) of both (middle and bottom component) cowpea mosaic virus rnas, using dideoxynucleotide termination of reverse transcription. sequence conservation is indicated, there being about 80% homology between the first 65 bases of each rna. although both rnas are polyadenylated, there is no aauaaa sequence as associated with most known polyadenylated mrnas of eukaryotes and viruses. however both rnas are u and a-rich in this region ...	1979	91160
tumor induction by agrobacterium tumefaciens prevented in vigna sinensis seedlings systemically infected by ribonucleic acid viruses.	cowpea (vigna sinensis) seedlings failed to develop tumors after being inoculated with crown gall bacteria (agrobacterium tumefaciens) if, at times earlier than 1 day later, they were inoculated on the primary leaves with a cowpea mosaic virus that systemically infects them. inoculation with buffer or with a virus that is restricted to a localized infection, or to which the cowpea is immune, did not interfere with the subsequent development of tumors. the virus infection did not appear to affect ...	1979	422243
in vitro replication of cowpea mosaic virus rna iii. template recognition by cowpea mosaic virus rna replicase.	cowpea mosaic virus (cpmv) rna replicase has been purified about 200-fold from cpmv-infected vigna unguiculata leaves. optimal reaction conditions for replicase activity have been established that allow rna synthesis to proceed for at least 15 h. using a polymerase assay under conditions optimal for cpmv rna-directed rna synthesis, all natural rna species tested appeared to be able to direct the incorporation of labeled ribonucleotides, whereas synthetic homoribopolymers were either inactive or ...	1979	16789172
genome-associated proteins of comoviruses.	previously, a protein has been reported to be associated with the rnas of cowpea mosaic virus. here we present evidence for genome-associated proteins of other comoviruses: squash mosaic virus, echtes ackerbohnemosaik-virus, and another strain of cowpea mosaic virus. although the proteins and protein-oligonucleotide complexes derived from the rnas of these viruses showed similar patterns of electrophoretic mobility, two-dimensional chromatograms of their tryptic peptides were distinct. chromatog ...	1979	18631616
evidence for intrastrand complementation in cowpea mosaic virus infection.	in supplementation tests both middle component (m)-rna and bottom component (b)-rna of cowpea mosaic virus mutant n142 were shown to carry mutations affecting local symptoms in bean and cowpea. the m- and b-rna mutations were separately incorporated into the two reciprocal hybrids of n142 and wild-type sb, designated as m142bsb and msbv142. mixtures of the two hybrids induced normal local symptoms in bean and cowpea as a result of reassortment of components. this was also the case with a mixture ...	1979	18631625
further genetic analysis of a temperature-sensitive mutant of cowpea mosaic virus.	the two reciprocal hybrids of wild-type cowpea mosaic virus (sb) and the temperature-sensitive mutant n168 were constructed. symptoms of both hybrids differed from those of the parent strains in three differential hosts indicating that n168 carries mutations in both components and that symptoms result from interactions between components. the occurrence of one or more temperature-sensitive mutations in the middle-component rna was confirmed. in vitro recombination of the hybrids yielded isolates ...	1979	18631621
nucleotide sequences adjacent to the proteins covalently linked to the cowpea mosaic virus genome. sequence determination after labelling in vitro using rna ligase.	the sequences of the first 17 nucleotides of cowpea mosaic virus middle and bottom rnas adjacent to the covalently-linked proteins have been determined. sequences of the oligonucleotides, produced by complete t1 rnase digestion, were established after labelling of the 3' termini in vitro using rna ligase. both sequences are a/u-rich, the first nine nucleotides being identical.	1979	116852
synthesis and proteolytic processing of cowpea mosaic virus proteins in reticulocyte lysates.		1979	462814
replication of cowpea mosaic virus in protoplasts isolated from immune lines of cowpeas.	in previous work, some lines from a collection of cowpeas (vigna unguiculata, walp.) were found to be immune to a cowpea mosaic virus strain (cpmv-sb) under specified conditions. at 24 hr after inoculation, protoplasts from a susceptible and most immune lines were sources of similar amounts of virus, but very little virus was recovered from protoplasts of line arlington. now we have compared the responses of arlington, several other immune lines, a local lesion host (a selection out of the cowpe ...	1979	18627895
the inhibition of cowpea mosaic virus replication by actinomycin d.		1979	425319
similar sequences from the 5' end of cowpea mosaic virus rnas.	similar, large (n approximately 40) oligonucleotides are released from each of the two cowpea mosaic virus genomic rnas by digestion with ribonuclease t1. each large oligonucleotide was radiolabeled at the 3' end, and the nucleotide sequence was determined by base-specific partial degradation and analysis of the fragments. specific deoxyoligonucleotides that are complementary to a portion of each large oligonucleotide were primers in reverse transcription reactions with intact virion rna as temp ...	1980	18631723
the genome-linked protein of cowpea mosaic virus is coded by rna from the bottom component.	it has recently been shown that rna from the bottom component of cowpea mosaic virus is capable of self-replication in cowpea mesophyll protoplasts, providing a tool for the investigation of the contribution of each rna strand toward viral multiplication. evidence is presented here, using this system, to show that the genome-linked protein is coded by the rna from the bottom component. as the replicase function is coded by this rna, the results remain consistent with the involvement of the genom ...	1980	18631720
crystalline cowpea mosaic virus.	crystals of cowpea mosaic virus displaying a high degree of order have been grown in two different forms. hexagonal crystals, space group p6(1)22 or p6(5)22 with a = 450 a and c = 1038 a containing six virus particles per cell, have been grown in sodium citrate buffer at ph 4.9. each particle has four nearest neighbors at 284 a. cubic crystals, with space group i23 and a = 308 a , containing two particles per cell were grown from ammonium sulfate at ph 4.9. in the cubic crystals, the tetrahedral ...	1980	18631640
lack of specificity of virus-stimulated plant rna-dependent rna polymerases.	rna-dependent rna polymerase preparations from tobacco and cowpea plants, either uninfected, or infected with tobacco necrosis or cowpea mosaic virus, were tested for their capability to bind radioactive viral or other rnas or polynucleotides. the limited binding of up to 30% of all rnas tested was found to be completely nonspecific in regard to any infecting virus, and it was nonspecifically diminished by excess of other unlabeled rnas. these data are in line with our previous conclusion that p ...	1980	18631634
expression of bottom component rna of cowpea mosaic virus in cowpea protoplasts.	upon inoculation of cowpea protoplasts with the bottom component of cowpea mosaic virus, at least six virus-induced proteins (with sizes of 170, 110, 87, 84, 60, and 32 kilodaltons) are synthesized, but not the capsid proteins (37 and 23 kilodaltons). these bottom-component-induced proteins were studied with respect to their genetic origin and mode of synthesis. the analyses were based on their electrophoretic peptide patterns resulting from partial digestion with staphylococcus aureus protease ...	1980	16789203
comparison of in vivo and in vitro translation of cowpea mosaic virus rnas.		1981	7236272
crystallographic studies of cowpea mosaic virus by electron microscopy and x-ray diffraction.		1981	7241643
the location of the first aug codons in cowpea mosaic virus rnas.	we have made use of the known sequence of the 5' ends of both cpmv rnas to synthesise an oligodeoxynucleotide which can prime second-strand dna synthesis on full-length cdna copies of both rnas. by priming synthesis in the presence of dideoxynucleoside triphosphates, we have determined the positions of the first aug codons in each rna. these occur at positions 115 and 207 on m and b rna respectively. by using a cloned double-stranded dna fragment derived from near the 5' end of m rna as a primer ...	1982	6897113
purification of a host-encoded rna-dependent rna polymerase from cowpea mosaic virus-infected cowpea leaves.	a membrane-bound rna-dependent rna polymerase from cowpea mosaic virus (cpmv)-infected cowpea leaves (vigna unguiculata) has been purified 15,000-fold by deae-sepharose cl-6b chromatography, affinity chromatography on poly(u)-sepharose 4b, and glycerol gradient centrifugation. particularly, poly(u)-sepharose 4b chromatography was a very efficient purification step and, in addition, achieved the separation of a host-encoded terminal uridylyl transferase activity from the rna polymerase activity. ...	1982	18635112
nitrate reductase activity in cowpea mosaic virus infected cowpea plant parts.		1982	6184966
expression of middle-component rna of cowpea mosaic virus: in vitro generation of a precursor to both capsid proteins by a bottom-component rna-encoded protease from infected cells.	the expression of the middle-component (m) rna of cowpea mosaic virus was studied by means of in vitro translation. in both the wheat germ extract and the rabbit reticulocyte lysate, m rna was translated into two overlapping polypeptides of 95 and 105 kilodaltons. incubation of these polypeptides with 30,000 x g supernatant fractions from cowpea mesophyll protoplasts inoculated with complete virus or with separate bottom (b) components alone resulted in extensive processing, yielding polypeptide ...	1982	16789216
antibodies against the genome-linked protein vpg of cowpea mosaic virus recognize a 60,000-dalton precursor polypeptide.	we have prepared a rabbit antiserum specifically directed against the genome-linked protein (vpg) of cowpea mosaic virus by injecting an hydrolysate of purified virion rna. using this antiserum as a probe in combination with "western" (protein) blots of subcellular fractions of cowpea mosaic virus-infected cowpea (vigna unguiculata) cells, we have detected a bottom component rna-encoded, 60,000-dalton polypeptide which is membrane bound and presumably represents the immediate precursor of vpg.	1982	16789217
expression of the bottom-component rna of cowpea mosaic virus: evidence that the 60-kilodalton vpg precursor is cleaved into single vpg and a 58-kilodalton polypeptide.	in cowpea protoplasts infected with cowpea mosaic virus, a bottom-component (b) rna-encoded 60-kilodalton (60k) polypeptide is synthesized, which is membrane-bound and represents the direct precursor to the genome-bound protein vpg. the relationship between this vpg precursor and other b-rna-encoded polypeptides was studied. digestion of the b-rna-encoded 170k and 84k polypeptides with staphylococcus aureus protease v8 and subsequent analysis of the generated peptides with antiserum against vpg ...	1982	16789223
cowpea mosaic virus-encoded protease does not recognize primary translation products of m rnas from other comoviruses.	the protease encoded by the large (b) rna segment of cowpea mosaic virus was tested for its ability to recognize the in vitro translation products of the small (m) rna segment from the comoviruses squash mosaic virus, red clover mottle virus, and cowpea severe mosaic virus (cpsmv, strains dg and ark), and from the nepovirus tomato black ring virus. like m rna from cowpea mosaic virus, the m rnas from squash mosaic virus, red clover mottle virus, cpsmv-dg, and cpsmv-ark were all translated into t ...	1982	16789228
the synthesis and processing of the proteins of bean pod mottle virus in rabbit reticulocyte lysates.	translation of the two rna components (b-rna and m-rna) of bean pod mottle virus (bpmv) in rabbit reticulocyte lysates resulted in the formation of a specific set of proteins. among the products formed was a viral protease that catalyzed the cleavage of two precursor proteins coded by m-rna. the protease showed some specificity for bpmv proteins in that it did not cleave the proteins of cowpea mosaic virus (cpmv), which is related to bpmv. conversely, the synthesized bpmv precursor proteins were ...	1982	18638812
ultrastructure of mixed plant virus infection: bean yellow mosaic virus with cowpea severe mosaic virus or cowpea mosaic virus in bean.	ultrastructural responses of bean leaf cells simultaneously infected with two morphologically distinct rna viruses, cowpea mosaic virus (cpmv) and bean yellow mosaic virus (bymv), or cowpea severe mosaic virus (csmv) and bymv, were studied in situ. the major effects on cells infected with two viruses included: (1) association of virus group-specific cytoplasmic inclusions characteristic of each virus; (2) close association of virions into specifically arranged aggregates in which cpmv or csmv ic ...	1983	18638866
orientation of the cleavage map of the 200-kilodalton polypeptide encoded by the bottom-component rna of cowpea mosaic virus.	the genomic organization of the bottom-component rna of cowpea mosaic virus was studied. in vivo, this rna encodes at least eight different polypeptides of 170, 110, 87, 84, 60, 58, 32, and 4 kilodaltons (k), the last polypeptide representing the genome-bound protein vpg. in rabbit reticulocyte lysates, bottom-component rna is translated into a 200k polypeptide which is then processed to give the 32 and 170k polypeptides also found in vivo. by pulse-labeling the 200k primary translation product, ...	1983	16789243
translational stability of plant viral rnas microinjected into living cells. influence of a 3'-poly(a) segment.	three different alternative structural features have been shown to be present at the 3' terminus of plant viral rnas: (a) a poly(a) track, (b) a trna-like structure, (c) no special structural or sequence characteristic. we have compared the translational stability after injection into frog oocytes of a representative of each type: (a) the small genomic rna (m-rna) of cowpea mosaic virus (cpmv), (b) the subgenomic mrna for coat protein (rna 4) of brome mosaic virus (bmv), (c) the subgenomic mrna ...	1983	6681761
comparison of capsids and nucleocapsids from cowpea mosaic virus-infected cowpea protoplasts and seedlings.	extracts of cowpea mosaic virus (cpmv)-infected cowpea (vigna unguiculata) protoplasts were applied to an anion-exchange agarose resin. both capsid-like and virion-like particles (collectively designated d-vlp) were present in the nonabsorbed fraction, although purified capsids and virions from protoplasts and from plants were absorbed irreversibly under the same conditions. the larger of the two capsid proteins, l protein, behaved similarly during electrophoretic analyses regardless of protopla ...	1983	18639118
the spherically averaged structures of cowpea mosaic virus components by x-ray solution scattering.	the x-ray diffraction patterns of the four components of cowpea mosaic virus isolated from a cesium chloride gradient were measured, using film methods, to 30 a resolution. diffraction patterns were analyzed by fitting computed two-shell spherical models to the observed data. the fitting procedure was applied to data to 80 a resolution to avoid the nonspherical contribution to the pattern observed at higher resolution. at ph 7.0 all four components displayed the same external spherically average ...	1983	18638997
the cowpea mosaic virus rna replication complex and the host-encoded rna-dependent rna polymerase-template complex are functionally different.	purification of the putative cowpea mosaic virus (cpmv) rna replicase previously started with an rna-dependent rna polymerase activity which had been solubilized from a crude membrane fraction of cpmv-infected cowpea leaves by extraction with a mg2+-deficient buffer. this led to the identification of a host-encoded, 130,000-dalton monomeric enzyme, the activity of which was highly enhanced upon infection. as the role of this enzyme in viral replication was questionable, we reverted to the templa ...	1983	18638890
the nucleotide sequence of cowpea mosaic virus b rna.	the complete sequence of the bottom component rna (b rna) of cowpea mosaic virus (cpmv) has been determined. restriction enzyme fragments of double-stranded cdna were cloned in m13 and the sequence of the inserts was determined by a combination of enzymatic and chemical sequencing techniques. additional sequence information was obtained by primed synthesis on first strand cdna. the complete sequence deduced is 5889 nucleotides long excluding the 3' poly(a), and contains an open reading frame suf ...	1983	16453487
primary structure and gene organization of the middle-component rna of cowpea mosaic virus.	middle component rna (m rna) of cowpea mosaic virus (cpmv) was transcribed into cdna and double-stranded cdna was inserted into the ecori site of plasmid pbrh2. the nucleotide sequence of inserts was determined, after subcloning in bacteriophages m13mp7, m13mp8 or m13mp9, by the dideoxy chain termination method. the complete sequence of cpmv m rna, up to the poly(a) tail, is 3481 nucleotides long. the sequence contains a long open reading frame starting at nucleotide 161 from the 5' terminus and ...	1983	6641721
evidence that the 32,000-dalton protein encoded by bottom-component rna of cowpea mosaic virus is a proteolytic processing enzyme.	translation of middle-component rna of cowpea mosaic virus in vitro produced two polypeptides of 95 and 105 kilodaltons (95k and 105k, respectively) with overlapping amino acid sequences, which were specifically cleaved by a protease encoded by the bottom-component rna. the proteolytic cleavage was studied by the addition of antibodies raised against various bottom-component rna-encoded proteins to extracts prepared from bottom-component rna-inoculated cowpea protoplasts. since antiserum to the ...	1984	16789248
purification of cowpea mosaic virus rna replication complex: identification of a virus-encoded 110,000-dalton polypeptide responsible for rna chain elongation.	an endogenous cowpea mosaic virus (cpmv) rna-protein complex (cpmv replication complex) capable of elongating in vitro preexisting nascent chains to full-length viral rnas has been solubilized from the membrane fraction of cpmv-infected cowpea leaves using triton x-100 and purified by sepharose 2b chromatography and glycerol gradient centrifugation in the presence of triton x-100. analysis of the polypeptide composition of the complex by nadod-so(4)/page and silver staining revealed major polype ...	1984	16593443
the rna-dependent rna polymerase of cowpea is not involved in cowpea mosaic virus rna replication: immunological evidence.	the rna-dependent rna polymerase (rdrp) of plants has been proposed to act as core rna polymerase in plant viral rna replication. an antiserum directed against the host-encoded rdrp from cowpea leaves was applied to examine a possible role of this enzyme in cowpea mosaic virus (cpmv) rna replication. the amount of host-encoded rdrp increased more than 20-fold in cowpea leaf cells infected with cpmv. in striking contrast, no increase of rdrp was found to accompany cpmv rna replication in cowpea m ...	1984	18639802
proteolytic processing of the proteins translated from the bottom component rna of cowpea mosaic virus. the primary and secondary cleavage reactions.	the products of translation of cowpea mosaic virus b-rna in rabbit reticulocyte lysates are proteolytically cleaved to form a specific set of proteins. the primary cleavage occurs as nascent peptide chains elongate to a size of about 150 kilodaltons yielding a 32k protein and, upon chain completion, a 170k protein. this cleavage reaction is inhibited by 3 mm iodoacetamide. the 170k protein, in turn, is cleaved to yield either of two pairs of proteins, a 110k and 60k pair or a 87k and 84k pair. t ...	1984	6699013
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
similarity in gene organization and homology between proteins of animal picornaviruses and a plant comovirus suggest common ancestry of these virus families.	the amino acid sequences deduced from the nucleic acid sequences of several animal picornaviruses and cowpea mosaic virus (cpmv), a plant virus, were compared. good homology was found between cpmv and the picornaviruses in the region of the picornavirus 2c (p2-x protein), vpg, 3c pro (proteinase) and 3d pol (rna polymerase) regions. the cpmv b genome was found to have a similar gene organization to the picornaviruses. a comparison of the 3c pro (proteinase) regions of all of the available picorn ...	1984	6384934
rna and capsid accumulation in cowpea protoplasts that are resistant to cowpea mosaic virus strain sb.	leaf protoplasts from the arlington line of cowpea (vigna unguiculata) support only a limited increase of cowpea mosaic virus strain sb (cpmv-sb), whereas cowpea severe mosaic virus, another member of the comovirus group, replicates efficiently in arlington cowpea protoplasts. cpmv-sb replicates efficiently in protoplasts of cowpea line blackeye 5. some characteristics of the virus-specific resistance of arlington protoplasts to cpmv-sb are reported. differences between progeny cpmv-sb from arli ...	1984	6485253
detection of double-stranded rna by serologically specific electron microscopy.	details of a procedure for detecting double-stranded rna (dsrna) in virus and viroid infected tissue extracts using serologically specific electron microscopy are given. a method for staining dsrna, based on in situ formation of uranyl phosphate, that consistently permits the examination of dsrna by electron microscopy without shadowing with heavy metals, is described. the method provides for routine assays for dsrna in crude extracts without the variable results associated with shadowing proced ...	1984	6530480
study of the genetic organisation of a plant viral rna genome by in vitro expression of a full-length dna copy.	the genetic approach for elucidating functions encoded by rna plant viruses has been hampered by the lack of methods to select desired mutants following random mutagenesis. an alternative might be to copy rna genomes into dna and use methods for site-directed mutagenesis to modify specific regions of the dna copy. transcription of the dna copy will subsequently produce viral rna with desired mutations. we have constructed a full-length dna copy of the smaller of the two cowpea mosaic virus (cpmv ...	1984	6549293
homologous sequences in non-structural proteins from cowpea mosaic virus and picornaviruses.	computer analyses have revealed sequence homology between two non-structural proteins encoded by cowpea mosaic virus (cpmv), and corresponding proteins encoded by two picornaviruses, poliovirus and foot-and-mouth disease virus. a region of 535 amino acids in the 87-k polypeptide from cpmv was found to be homologous to the rna-dependent rna polymerases from both picornaviruses, the best matches being found where the picornaviral proteins most resemble each other. additionally, the 58-k polypeptid ...	1984	16453518
cowpea mosaic virus vpg: sequencing of radiochemically modified protein allows mapping of the gene on b rna.	a partial amino acid sequence of cowpea mosaic virus (cpmv) vpg radiochemically modified by chloramine-t and bolton-hunter reagent has been determined. vpg covalently bound to viral rna chains (vpg-rna) was iodinated with chloramine-t and bolton-hunter reagent to label tyrosine and lysine residues, respectively. [i]vpg-rna was digested with nuclease p1 and the resulting [i]vpg-pu was purified by sds-polyacrylamide gel electrophoresis and subjected to automated edman degradation. control experime ...	1984	16453534
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
protein bound to the genome rnas of cowpea mosaic virus.		1984	215411
independent replication of cowpea mosaic virus bottom component rna: in vivo instability of the viral rnas.	we compared the accumulation of cowpea mosaic virus (cpmv) rnas after inoculation of cowpea and chenopodium quinoa protoplasts with bottom (b) or middle (m) component virions alone, or with a mixture of the m and b components. rna extracted from infected protoplasts was subjected to quantitative spot hybridization after electrophoresis and blotting. compared to the complete m plus b mixture, the b inoculum induced (1) a reduced rate and extent of accumulation of b-rna of both the (+) and (-) pol ...	1985	18640533
isolation of a fraction from cauliflower mosaic virus-infected protoplasts which is active in the synthesis of (+) and (-) strand viral dna and reverse transcription of primed rna templates.	sub-cellular fractions, isolated from cauliflower mosaic virus (camv)-infected turnip protoplasts, are capable of synthesising camv dna in vitro on an endogenous template and of reverse transcribing oligo dt-primed cowpea mosaic virus rna. the activity was not detected in mock-inoculated protoplasts. in vitro-labelled dna hybridized to single-stranded m13 clones complementary to the putative origins of (-) and (+) strand camv dna synthesis and to restriction endonuclease fragments encompassing m ...	1985	2409536
thermal stability of cowpea mosaic virus components: differential scanning calorimetry studies.	differential scanning calorimetry studies show that the thermal stability of cowpea mosaic virus (cpmv) is ph dependent in the ph range 5 to 8. the four different components of cpmv, top (protein shell devoid of rna), middle (virus particle containing the smaller rna), bottom upper and bottom lower (virus particle containing the larger rna), are stable up to 64-70 degrees at ph 5.0 and up to 43-46 degrees at ph 8.25. these components did not exhibit any difference in their thermal stability betw ...	1985	4036006
the structure of cowpea mosaic virus replicative form rna.	the structure of cowpea mosaic virus (cpmv) replicative form (rf) rna has been investigated by in vitro labelling at the 5' and 3' termini. the results indicate that the 3' termini of the minus (-) strands of the rfs from both m and b rna (rf-m and rf-b) are exact complements of the corresponding 5' sequences of the virion rnas. the 5'-labelling studies revealed that both rf-m and rf-b have vpg linked to poly(u) at the 5' ends of the (-) strands and also show that there is heterogeneity in the l ...	1985	18640531
isolation and characterization of two temperature-sensitive mutants of cowpea mosaic virus.	two temperature-sensitive mutants of cowpea mosaic virus have been isolated following nitrous acid mutagenesis. one mutant, 8-14, was shown to have a temperature-sensitive defect in the b component rna. the location of the temperature-sensitive defect of the other mutant, 8-10, was not unambiguously determined. no virus-specific proteins were detected in leaves inoculated with the mutants and grown at the restrictive temperature. dot blot analysis and infectivity assays indicated that reduced am ...	1985	18639840
1h, 13c, and 31p nuclear magnetic resonance studies of cowpea mosaic virus: detection and exchange of polyamines and dynamics of the rna.	1h and 13c nmr studies on cowpea mosaic virus (cpmv) revealed that polyamines are present in the middle (m) and upper bottom (bu) components obtained by cscl density gradient centrifugation but not in the top (t) component; the lower bottom (bl) component contains trace amounts of polyamine. dialysis of the bl component against spermidine led to incorporation of spermidine which gave rise to nmr peaks very similar to those observed with the natural m and bu components. nmr results conclusively d ...	1985	3976178
determination of the proteolytic processing sites in the polyprotein encoded by the bottom-component rna of cowpea mosaic virus.	the bottom-component rna (b-rna) of cowpea mosaic virus is expressed by the production of a approximately 200,000-dalton polyprotein (200k polyprotein), from which the functional proteins are formed by specific proteolytic cleavages. partial amino-terminal sequences of the various b-rna-encoded proteins have now been determined. comparison of the information obtained with the b-rna sequence allowed the localization of the coding regions for these proteins on b-rna, the calculation of their preci ...	1986	16789257
the primary structure of red clover mottle virus middle component rna.	the primary structure of middle component rna of red clover mottle virus (rcmv) has been determined. the rna is polyadenylated, has a small protein (vpg) covalently linked to its 5' terminus and consists of 3543 nucleotides. the rna possesses a single long open reading frame which can code for a polypeptide of molecular weight 109,452. comparison of the 3' terminal sequence of the m rna with that of the homologous b rna reveals a high degree of sequence conservation in this area. computer-assist ...	1986	18640659
molecular cloning and sequence determination of the genomic regions encoding protease and genome-linked protein of three picornaviruses.	to investigate the degree of similarity between picornavirus proteases, we cloned the genomic cdnas of an enterovirus, echovirus 9 (strain barty), and two rhinoviruses, serotypes 1a and 14lp, and determined the nucleotide sequence of the region which, by analogy to poliovirus, encodes the protease. the nucleotide sequence of the region encoding the genome-linked protein vpg, immediately adjacent to the protease, was also determined. comparison of nucleotide and deduced amino acid sequences with ...	1986	3512851
cleavage of a viral polyprotein by a cellular proteolytic activity.	the 200,000-dalton polyprotein encoded by the bottom component rna of cowpea mosaic virus was synthesized in rabbit reticulocyte lysates, and this in vitro-synthesized protein was isolated from the lysate reaction mixture by sucrose density gradient centrifugation. incubation of the isolated polyprotein with buffer caused no change in the protein, but incubation with reticulocyte lysates or with fractionated lysate proteins resulted in cleavage of the protein into the expected cleavage products ...	1986	3003387
proteolytic activity of the cowpea mosaic virus encoded 24k protein synthesized in escherichia coli.	the function of the 24-kilodalton (24k) protein encoded by cowpea mosaic virus (cpmv) has been studied by constructing a bacterial expression plasmid that contained a cloned chimeric segment consisting of partial dna copies of cpmv m-rna (including sequences coding for both capsid proteins) and b-rna (including sequences coding for the 24k protein). viral sequences were transcribed from the phage t7 promoter phi 10 of plasmid pt7-6 using t7-rna polymerase expressed from plasmid pgp1-2 present in ...	1987	3300014