| evidence for the release of 28 s rna from turnip yellow mosaic virus heated in vitro. | | 1968 | 5680009 |
| optical investigations on double stranded ribonucleic acid from turnip yellow mosaic virus. | | 1968 | 5713395 |
| the incorporation of radiolabeled polyamines and methionine into turnip yellow mosaic virus in protoplasts from infected plants. | turnip yellow mosaic virus contains large amounts of nonexchangeable spermidine and induces an accumulation of spermidine in infected chinese cabbage. by 7 days after inoculation, a majority of protoplasts isolated from newly emerging leaves stain with fluorescent antibody to the virus. these protoplasts contain 1-2 x 10(6) virions per cell and continue to produce virus in culture for at least 48 hr. [14c]spermidine (10 microm) was taken up by these cells in amounts comparable to the original en ... | 1985 | 4060587 |
| infection of phaseolus vulgaris with alfalfa mosaic virus: inhibitory effect of pretreatment with turnip yellow mosaic virus. | | 1969 | 5777564 |
| the effects of dicyclohexylamine on polyamine biosynthesis and incorporation into turnip yellow mosaic virus in chinese cabbage protoplasts infected in vitro. | we have reported (r. balint and s. s. cohen, 1985, virology 144, 181-193) that protoplasts from plants infected with turnip yellow mosaic virus (tymv) continue to produce virus in culture and that newly formed virus particles contained predominantly newly synthesized spermidine and spermine. inhibition of spermidine synthesis by dicyclohexylamine (dcha), however, led to incorporation of preexisting spermidine and increased amounts of spermine into newly formed virions. we now report similar resu ... | 1985 | 4060588 |
| in situ breakage of turnip yellow mosaic virus rna and in situ aggregation of the fragments. analysis of successive stages. | | 1969 | 5799580 |
| degradation of turnip yellow mosaic virus by freezing and thawing in vitro: a new method for studies on the internal organization of the viral components and for isolating native rna. | | 1969 | 5799582 |
| nucleic acid-protein interactions in turnip yellow mosaic virus. | mild alkaline treatment induces the formation of a specific rna complex inside turnip yellow mosaic virus. dialysis at ph 4.5 destroys this complex inside the capsid, but does not destroy complexes that have been removed from their capsids. these facts were interpreted in terms of a breakage and subsequent re-formation of rna-protein links. in combination with supporting potentiometric data, they suggest histidinyl-phosphate salt links or carboxylate-amino hydrogen bonds, or both, as the princip ... | 1969 | 5821214 |
| equilibrium sedimentation of turnip yellow mosaic virus. | sedimentation equilibrium was achieved with turnip yellow mosaic virus at low speeds (600 rpm) in a magnetic ultracentrifuge. the experiments were carried out in the newly installed constant-speed rotor, equipped with automatic control and an electromagnetic drive. a particle mass of 5.55 x 10(6) daltons was calculated for the virus at vanishing concentrations, in essential agreement with the earlier results using the more tedious procedure with a freely coasting rotor. in order to interpret the ... | 1974 | 4530267 |
| physicochemical studies on turnip-yellow-mosaic virus. homogeneity, relative molecular masses, hydrodynamic radii and concentration-dependence of parameters in non-dissociating solvents. | turnip-yellow-mosaic virus, with its stable, highly spherical and monodisperse character, was chosen as a suitable model substance with which to test hydrodynamic theories of transport. sedimentation coefficients, diffusion coefficients (obtained through photon correlation spectroscopy) and viscosities were measured accurately as a function of concentration in well-defined and nearly neutral buffer systems. ancillary information was also obtained from very-low-speed sedimentation-equilibrium exp ... | 1985 | 4074323 |
| a circular dichroism study of the turnip yellow mosaic virus-rna. | we examined the circular dichroism spectra of intact turnip yellow mosaic virus, freezed/thawed virus, empty capsid particles, and phenol extracted rna. the circular dichroism signal of the empty capsid was found to contribute for less than 1% to the circular dichroism of the virus. differences in the circular dichroism spectra indicate that tymv-rna exhibits different conformations when it is in situ in the virus, when it has been ejected by freezing/thawing and when it has been phenol extracte ... | 1985 | 4084608 |
| the significance of chloroplast abnormalities associated with infection by turnip yellow mosaic virus. | | 1970 | 4099065 |
| biochemical and biophysical analysis of pseudoknot-containing rna fragments. melting studies and nmr spectroscopy. | three overlapping rna fragments containing the pseudoknot, as found in the trna-like structure of turnip yellow mosaic virus (tymv) rna, have been isolated and purified. site-directed cleavage of tymv rna by rnase h, followed by ammonium sulphate precipitation and ion-exchange hplc, yielded a pure preparation of a 3'-terminal, 112-nucleotide tymv rna fragment. transcription of tymv cdna by t7 rna polymerase, resulted in the isolation of an 88-nucleotide fragment. finally, a 44-nucleotide fragmen ... | 1989 | 2776753 |
| nucleotide sequence of the ononis yellow mosaic tymovirus genome. | the nucleotide sequence of the genome of ononis yellow mosaic tymovirus (oymv) has been determined. the genome is single-stranded rna, 6211 nucleotides long, and has three main open reading frames (orfs), two of them overlapping. the largest orf (nucleotides 179-5509) encodes a polyprotein of 1776 amino acid residues that has sequence similarities with polymerases of other viruses with rna genomes. the smaller overlapping orf (nucleotides 172-1965) encodes a protein of 597 amino acids of unknown ... | 1989 | 2800337 |
| ionic conditions for the cleavage of the trna-like structure of turnip yellow mosaic virus by the catalytic rna of rnase p. | the 3'-end of the rna genome of turnip yellow mosaic virus can form a pseudoknotted trna-like structure that can be recognized by several trna-specific enzymes. we have found that the catalytic rna component of bacillus subtilis rnase p can cleave this structure in unusually low ionic strength buffers at a site analogous to the 5'-end of an aminoacyl stem of a trna. most other precursors can only be processed under low ionic strength conditions if the rnase p holoenzyme is used; processing by th ... | 1988 | 3136161 |
| reconstitution of turnip yellow mosaic virus rna with tmv protein subunits. | | 1966 | 5916557 |
| the extraction of infectious, high molecular weight rna from turnip yellow mosaic virus with ethanol. | | 1966 | 5928792 |
| minor components associated with turnip yellow mosaic virus. | | 1966 | 5928798 |
| cytological changes induced by turnip yellow mosaic virus in chinese cabbage leaves. | | 1966 | 5938885 |
| valylation of trna-like transcripts from cloned cdna of turnip yellow mosaic virus rna demonstrate that the l-shaped region at the 3' end of the viral rna is not sufficient for optimal aminoacylation. | clones containing different lengths of cdna corresponding to the 3' region of turnip yellow mosaic virus rna were constructed and transcribed in vitro into the corresponding rnas. each transcript contained the l-shaped trna domain (n = 82) plus (i) in the case of 3 upstream sequences up to n = 93, 109 and 258; and (ii) in all cases an additional 6 nucleotide-stretch at the 5' end derived from the t7 promoter. the valylation of these molecules, as well as that of a fragment (n = 159) purified fro ... | 1988 | 3150675 |
| the ribonucleic acid content of turnip yellow mosaic virus. | | 1966 | 5961282 |
| novel reactions of rnaase p with a trna-like structure in turnip yellow mosaic virus rna. | a quasi-continuous double hellix, containing a pseudoknot and ending in a single-stranded region which contains cca, can be formed at the 3' terminus of the genomic rnas of certain plant viruses. m1 rna (the catalytic subunit) alone and the rnaase p holoenzyme from e. coli cleave the trna-like structure of tymv rna in vitro at the 5' side of the quasi-helical structure to generate 5' phosphate and 3' hydroxyl groups in the cleavage products. the intact pseudoknot structure in the substrate is no ... | 1988 | 3359488 |
| effects of 2-thiouracil on synthesis of double-stranded turnip yellow mosaic virus rna in cell-free extracts. | | 1966 | 5965737 |
| overlapping open reading frames revealed by complete nucleotide sequencing of turnip yellow mosaic virus genomic rna. | the complete nucleotide sequence of turnip yellow mosaic virus (tymv) genomic rna has been determined on a set of overlapping cdna clones using a sequential sequencing strategy. the rna is 6318 nucleotides long, excluding the cap structure. the genome organization deduced from the sequence confirms previous results of in vitro translation. a novel open reading frame (orf) putatively encoding a pro-rich and very basic 69k (k = kilodalton) protein is detected at the 5' end of the genome. it is ini ... | 1988 | 3399388 |
| nucleotide sequence comparisons of turnip yellow mosaic virus isolates from australia and europe. | the genomic sequences of four isolates of turnip yellow mosaic virus (tymv-cd) from australia, and three tymv-1 (type) and three tymv-2 (cauliflower) isolates from europe were compared by cdna-rna hybridization tests, by analysis of the fragments produced from cdna-rna hybrids by restriction endonuclease treatment, and by determining the 3' terminal nucleotide sequences of their coat protein mrnas. all three methods showed only slight differences (ca. 1%) between the mrna sequences of different ... | 1987 | 3426397 |
| in situ breakage of turnip yellow mosaic virus rna and in situ aggregation of the fragments. | | 1967 | 6022491 |
| [primary structure of turnip yellow mosaic virus protein. i. primary structure of water-soluble tryptic peptides]. | | 1970 | 5452677 |
| crystalline arrays of spherical particles in turnip yellow mosaic virus-infected cells. | | 1967 | 6028941 |
| interactions of mercuric chloride with turnip yellow mosaic virus: dissociation of the virus and reassociation of the reaction products. | | 1971 | 5543279 |
| virus strains and leaf ontogeny as factors in the production of leaf mosaic patterns by turnip yellow mosaic virus. | | 1967 | 6039957 |
| studies on the stabilizing forces of simple rna viruses. i. selective interference with protein-rna interactions in turnip yellow mosaic virus. | | 1971 | 5551394 |
| ribonuclease isozymes in chinese cabbage systemically infected with turnip yellow mosaic virus. | | 1968 | 5723669 |
| the effect of freezing on the structure of turnip yellow mosaic virus and a number of other simple plant viruses. an ultracentrifugal analysis. | | 1969 | 5791159 |
| virus infection and photosynthesis. 1. increased photophosphorylation by chloroplasts from chinese cabbage infected with turnip yellow mosaic virus. | | 1965 | 5850878 |
| [rna isolated from turnip yellow mosaic virus; acceptor of amino acids in the presence of bacterial enzymes]. | | 1965 | 5851009 |
| [properties of ribonucleic acids extracted from b. chinensis infected by turnip yellow mosaic virus]. | | 1965 | 5851011 |
| investigations on turnip yellow mosaic virus interactions with aliphatic mercurials. i. | | 1965 | 5851868 |
| valine specific trna-like structure in rnas of two viruses of turnip yellow mosaic virus group. | | 1972 | 4654402 |
| studies on the interaction of p-chloromercuribenzoate with turnip yellow mosaic virus. 3. involvement of the ribonucleic acid. | | 1965 | 5880968 |
| three-dimensional image reconstruction of turnip yellow mosaic virus. | | 1972 | 4660324 |
| turnip yellow mosaic virus-rna replicase: partial purification of the enzyme from the solubilized enzyme-template complex. | | 1974 | 4820886 |
| nucleotide sequence of a cloned cdna copy of tmv (cowpea strain) rna, including the assembly origin, the coat protein cistron, and the 3' non-coding region. | the cloned cdna derived from the 3' end of cowpea strain (cc) rna of tobacco mosaic virus (tmv) has been sequenced. substantial sequence information of 1,060 nucleotides from the 3' end of the rna reveals some interesting features: (1) the coat protein cistron corresponds to residues 210-701 from the 3' end. some errors in the amino acid sequence previously reported have been corrected and the revised total length of the coat protein is 162 amino acid residues. the capping site of the coat prote ... | 1981 | 6950195 |
| arrangement of protein subunits and the distribution of nucleic acid in turnip yellow mosaic virus. i. x-ray diffraction studies. | | 1966 | 5912046 |
| the sequence of early cytological changes in chinese cabbage leaf cells following systemic infection with turnip yellow mosaic virus. | | 1974 | 4833533 |
| arrangement of protein subunits and the distribution of nucleic acid in turnip yellow mosaic virus. ii. electron microscopic studies. | | 1966 | 5912047 |
| effect of pressure on the apparent specific volume of proteins. | the magnetic densimeter has been employed to measure the densities and apparent specific volumes of certain proteins in aqueous solutions as a function of pressure. the method gave values in satisfactory agreement with those found in the literature for aqueous electrolyte solutions. a change in apparent specific volume of the monomeric proteins, ribonuclease and turnip yellow mosaic virus and its capsid protein, at pressures up to 400 atmospheres at 20 degrees c was not observed within the preci ... | 1969 | 5257142 |
| valine-specific trna-like structure in turnip yellow mosaic virus rna. | the 3' terminal nucleotide of turnip yellow mosaic virus (tymv) rna (23-25 s) may be esterified with valine in the presence of atp and an enzyme preparation from escherichia coli. the nucleotide composition near the valine-binding site is different for tymv rna and trna(val) from cabbage, as shown by comparison of the valine adducts of nucleotides labeled with radioactive valine in t(1) rnase digests. consequently, host trna(val) is not involved in the observed charging of tymv rna with valine. ... | 1970 | 5274462 |
| on the origin of the mosaic induced by turnip yellow mosaic virus. | | 1966 | 5940377 |
| synthesis of double-stranded viral rna by cell-free extracts from turnip yellow mosaic virus-infected leaves. | | 1966 | 5961627 |
| structural similarity of artificial and natural top components of turnip yellow mosaic virus. | | 1966 | 5967285 |
| particle weight of turnip yellow mosaic virus. | | 1966 | 5967287 |
| expression of the turnip yellow mosaic virus proteinase in escherichia coli and determination of the cleavage site within the 206 kda protein. | the large non-structural polyprotein (206 kda) of turnip yellow mosaic tymovirus (tymv) undergoes auto-cleavage, producing n- and c-terminal proteins. here we show that the viral proteinase responsible for this event is active when produced in escherichia coli, as monitored in western blots by examining the generation of the c-terminal cleavage product after induction by iptg. the outer boundaries and critical amino acids of the proteinase domain were characterized by deletion analysis and site- ... | 1995 | 7595394 |
| binding and translation of turnip-yellow-mosaic-virus ribonucleic acid by skeletal-muscle ribosomes from normal and diabetic rats. | ribosomes from skeletal muscle of diabetic rats were less active than normal ribosomes in protein synthesis directed by turnip-yellow-mosaic-virus rna. the proportion of ribosomes from muscle of diabetic rats capable of binding turnip-yellow-mosaic-virus rna was greater than normal, but there was no difference in the equilibrium constants for the binding reaction. the turnip-yellow-mosaic-virus rna was bound preferentially to the small (40s) ribosomal subunit, whereas the decrease due to diabete ... | 1970 | 5451911 |
| simultaneous determination of viscosity and density of protein solutions by magnetic suspension. | the first results are reported with a magnetic suspension instrument for determination of the viscosity and density concurrently on small volumes (0.2 ml) of protein solution. reasonable agreement was obtained with literature values for the intrinsic viscosities and specific volumes (partial or isopotential) of serum albumin and ribonuclease in native solvents, and in 6 m guanidinium chloride with or without 2-mercaptoethanol. turnip yellow mosaic virus and myosin were also studied, the results ... | 1972 | 4506095 |
| structure of broad bean mottle virus. i. analysis of electron micrographs comparison with turnip yellow mosaic virus and its top component. | | 1967 | 6030027 |
| studies on the interaction of p-mercuribenzoate with turnip yellow mosaic virus. iv. conformational change, exposure of buried prototropic groups, and ph-induced degradation. | | 1967 | 6047630 |
| role of virus strains and leaf ontogeny in the production of mosaic patterns by turnip yellow mosaic virus. | | 1967 | 6082736 |
| immunochemical studies of turnip yellow mosaic virus--i. localization of four antigenic regions in the protein subunit. | | 1980 | 6160393 |
| length requirements for trna-specific enzymes and cleavage specificity at the 3' end of turnip yellow mosaic virus rna. | this paper describes the minimum length of the turnip yellow mosaic virus (tymv) rna necessary to fulfill the trna-like properties of the viral rna: 50 to 75 nucleotides and 86 nucleotides from the 3' end of tymv rna are sufficient for adenylation and valylation respectively by the escherichia coli system. the size of the trna-like fragments obtained in vitro in the presence of an e. coli, a reticulocyte or a chinese cabbage leaf extract has also been determined. among the major fragments libera ... | 1982 | 6176943 |
| immunochemical studies of turnip yellow mosaic virus--ii. localization of a viral epitope in the n-terminal residues of the coat protein. | | 1983 | 6188950 |
| comparison of three different cell-free systems for turnip yellow mosaic virus rna translation. | the two proteins of molecular weights 150,000 and 195,000 specific of turnip yellow mosaic virus (tymv) rna translation in reticulocyte lysates have now also been detected in two other cell-free systems programmed with tymv rna: the wheat germ extract and the ehrlich ascites cell-free system. the wheat germ extract contains proteases that affect the nascent tymv polypeptide chains. the specific post-translational maturation of the protein of molecular weight 195,000 known to occur in the reticul ... | 1983 | 6405803 |
| three-dimensional models of the trna-like 3' termini of some plant viral rnas. | various plant viral rnas possess a 3' terminus with trna-like properties. these viral rnas are charged with an amino acid upon incubation with the cognate aminoacyl-trna synthetase and atp. we have studied the structure of end-labelled 3'-terminal fragments of turnip yellow mosaic virus rna and brome mosaic virus rna 2 with chemical modifications of the adenosine and cytidine residues and with enzymatic digestions using rnase t1, nuclease s1 and the double-strand-specific ribonuclease from cobra ... | 1983 | 6628363 |
| evidence for the presence of a hole in the capsid of turnip yellow mosaic virus after rna release by freezing and thawing. decapsidation of turnip yellow mosaic virus in vitro. | turnip yellow mosaic virus (tymv) rna escapes from viral capsids after freezing and thawing the virus, and the remaining capsids look very similar to natural capsids in the electron microscope after negative staining [katouzian-safadi, m., favre, a., and haenni, a. l. (1980) eur. j. biochem. 112, 478-486]. in order to understand how an rna of 2 x 10(6) da (33% virus by weight) can escape from a compact protein shell we have compared artificial capsids formed after freezing tymv and natural capsi ... | 1983 | 6653559 |
| freeze-etching electron microscopy of serum lipoproteins. | the structure of serum lipoproteins in solution has been investigated by freeze-etching electron microscopy employing rapid freezing techniques. turnip yellow mosaic virus was used to demonstrate the performance of these techniques and their capability to provide information about the structure of particles in solution. low-density lipoproteins appeared to deviate markedly from a smooth spherical shape. instead, the outer layer of the particles appeared to consist of a small number of globules. ... | 1980 | 6772079 |
| the thermal stability and decapsidation mechanism of tymoviruses: a differential calorimetric study. | the thermal stability of virions present in purified suspensions of three tymoviruses, turnip yellow mosaic virus (tymv), belladonna mottle virus (belmv) and eggplant mosaic virus (emv) was investigated by microcalorimetry. virions are less stable than natural empty shells at 4.5 < or = ph < or = 8.5. polyvalent cations present in tymv stabilize the virions at ph < or = 5.0 only. virions decapsidate in three steps: i) the release of the viral rna, probably through a hole in the capsid; ii) the d ... | 1993 | 8286439 |
| autoradiography of 32p and 14c incorporation into protoplasts as a means of determining the percentage of virus infected protoplasts. | stripping film autoradiography (sfa) was used to measure percentage protoplast infection. control and infected protoplasts were incubated in the presence of [32p]orthophosphate or [14c]leucine fixed onto glass slides and placed in contact with a sensitive photographic emulsion. infected protoplasts were distinguished by blackened areas of exposed film which coincided with protoplasts containing labelled virus products. the use of sfa is demonstrated for two different virus/protoplast systems, na ... | 1983 | 6885954 |
| increased viral yield and symptom severity result from a single amino acid substitution in the turnip yellow mosaic virus movement protein. | turnip yellow mosaic virus is a positive-strand rna virus that produces light green or yellow-green mosaic symptoms in chinese cabbage plants. we have characterized a strain that produces nearly uniform yellow-green chlorosis in systemically infected chinese cabbage leaves. the increased symptom severity is due to the single nucleotide substitution u1888-->c, which results in a tyrosine to histidine substitution in the movement protein encoded by orf-69. coding by the overlapping orf-206 is not ... | 1993 | 8324245 |
| spermidine, an intrinsic component of turnip yellow mosaic virus. | the major polyamine of turnip yellow mosaic virus has been identified as spermidine by gas chromatography and mass spectrometry of the trifluoroacetamido derivative. very small amounts of putrescine and cadaverine, but not norspermidine, have been detected in the virus. the spermidine contents of numerous virus preparations were in the range 200-700 molecules per virion and were considerably in excess of those of spermine. the rna and spermidine contents of small amounts of the virus were determ ... | 1981 | 6946484 |
| faithful and efficient translation of homologous and heterologous mrnas in an mrna-dependent cell-free system from saccharomyces cerevisiae. | a cell-free protein synthesizing system from the yeast saccharomyces cerevisiae has been optimized for the translation of both homologous yeast mrna and for a number of heterologous eukaryotic mrnas. a significant increase in protein synthesis was observed when k(oac) rather than kcl was used as the source of k+ in the in vitro translation system. this was due primarily to an inhibitory effect oif cl-. the polyamine putrescine hydrochloride stimulated protein synthesis only at low mg2+ concentra ... | 1980 | 6997303 |
| genomic fragments of turnip yellow mosaic virus: appearance during infection. | | 1980 | 7004442 |
| portraits of viruses: turnip yellow mosaic virus. | | 1981 | 7026488 |
| large-scale purification of the 3'-oh-terminal trna-like sequence (n = 159) of turnip-yellow-mosaic-virus rna. | in order to undertake structural and functional studies on the 3'-terminal part of turnip yellow mosaic virus rna, a structure which can be specifically aminoacylated by valyl-trna synthetase, we have developed large-scale methods for purifying the trna-like sequence. several experimental approaches were tested. one procedure was retained enabling us to purify large quantities of the homogeneous trna-like fragment. starting from 1.5 g turnip yellow mosaic virus, one obtains 400 mg rna, which is ... | 1982 | 7067700 |
| the trna-like structure at the 3' terminus of turnip yellow mosaic virus rna. differences and similarities with canonical trna. | the 3' terminus of tymv rna, which possesses trna-like properties, has been studied. a 3' terminal fragment of 112 nucleotides was obtained by cleavage with rnase h after hybridization of a synthetic oligodeoxynucleotide to the viral rna. the accessibility of cytidine and adenosine residues was probed with chemical modification. enzymatic digestion studies were performed with rnase t1, nuclease s1 and the double-strand specific rnase from the venom of the cobra naja naja oxiana. a model is propo ... | 1982 | 7079175 |
| proteolytic maturation of the turnip-yellow-mosaic-virus polyprotein coded in vitro occurs by internal catalysis. | the genomic rna of turnip yellow mosaic virus is translated in vitro into two major high-molecular-weight proteins, the larger of which (mr 195 000) undergoes post-translational cleavage. the mechanism of formation of the primary cleavage products (mr 120 000 and mr 78 000) of the 195 000-mr protein has been examined. the fact that cleavage partly occurs at a rate insensitive to dilution of the 195 000-mr protein is suggestive of an intramolecular mechanism of proteolytic maturation. | 1982 | 7140768 |
| identification of binding sites of turnip yellow mosaic virus protein and rna by crosslinks induced in situ. | turnip yellow mosaic virus rna and protein could be crosslinked in situ by ultraviolet irradiation at ph 4.8 but not at ph 7.3, and by bisulphite treatment at ph 7.3. crosslinked peptides could be located in the primary structure of the viral coat protein. three regions were bound covalently by ultraviolet irradiation, and two of these three regions were bound also by bisulphite treatment. the yield of the crosslinking reaction could be high, indicating that almost all protein subunits of each v ... | 1980 | 7408843 |
| preferential translation of mrnas in an mrna-dependent reticulocyte lysate. | messenger rna competition experiments were performed in an mrna-dependent reticulocyte lysate using three kinds of mrna: rabbit globin mrna, calf eye lens mrna and rna of turnip yellow mosaic virus. our results indicate that at supersaturating concentrations of mrna preferential translation of certain mrna species can be observed. furthermore, the pattern of mrna selection by the translational apparatus suggests that the rate of translation of different mrna species is limited by different compo ... | 1980 | 7408873 |
| effect of freezing and thawing on the structure of turnip yellow mosaic virus. | the uncoating of turnip yellow mosaic virus in vitro induced by freezing and thawing has been investigated using a variety of biochemical techniques including the aminoacylation capacity of the viral rna and the ability of the rna to stimulate protein synthesis, as well as physico-chemical techniques such as sucrose gradient centrifugation and electron microscopy by negative staining. in particular a fluorescence test has been developed that can serve as a routine method to quantify the rna libe ... | 1980 | 7460931 |
| tubular structures associated with turnip yellow mosaic virus in vivo. | plants infected with a necrotic strain of turnip yellow mosaic virus contain tubes averaging about 80 millimicrons in diameter and attaining 3 microns in length. the main constituent of these tubes is a protein that is related chemically and immunologically to the protein of the virus. the tubes are composed of hexagonally packed hexagonal subunits resembling the hexamer protein subunits of the virus particles and are probably helical in construction. | 1967 | 6028045 |
| histidylation by yeast hisrs of trna or trna-like structure relies on residues -1 and 73 but is dependent on the rna context. | residue g-1 and discriminator base c73 are the major histidine identity elements in prokaryotes. here we evaluate the importance of these two nucleotides in yeast histidine aminoacylation identity. deletion of g-1 in yeast trna(his) transcript leads to a drastic loss of histidylation specificity (about 500-fold). mutation of discriminator base a73, common to all yeast trna(his) species, into g73 has a more moderate but still significant effect with a 22-fold decrease in histidylation specificity ... | 1994 | 7800496 |
| coding density of the turnip yellow mosaic virus genome: roles of the overlapping coat protein and p206-readthrough coding regions. | more than one-third of the turnip yellow mosaic virus (tymv) genome simultaneously encodes two orfs. we have investigated the functions of the overlapping coat protein orf and readthrough domain of orf-206 in the 3' region of the genome. tymc-206 rna, in which a second stop codon has been positioned to prevent orf-206 readthrough, induced infections in protoplasts and plants that were indistinguishable from wild type. orf-206 readthrough is thus nonessential. nevertheless, tymv-221 rna, in which ... | 1995 | 7831796 |
| physicochemical properties of four tymoviruses. | isoelectric point (pi), free mobility and retardation coefficient (kr) of turnip yellow mosaic virus (tymv), erysimum latent virus (elv), belladonna mottle virus (belmv) and scrophullaria mottle virus (scrmv) have been studied. the use of ferguson plots for the physical identification of these four viruses and for confirmation of their identity is discussed. for tymv, elv, belmv and scrmv the pi values of 3.64, 4.73, 6.25 and 3.95, respectively, were found. using kr the differences between the d ... | 1993 | 7905242 |
| preferential replication of defective turnip yellow mosaic virus rnas that express the 150-kda protein in cis. | the turnip yellow mosaic virus genome encodes two proteins (the 150-kda and 70-kda proteins) that are proteolytically released from a single precursor and which are essential for rna replication. genomes with mutations in either of these coding regions were defective for independent replication in turnip protoplasts. the replication in trans of genomes with mutations in each region was studied by coinoculation with either a helper genome that carries a deletion in the coat protein gene, or with ... | 1994 | 8032251 |
| identification of the essential cysteine and histidine residues of the turnip yellow mosaic virus protease. | the nonstructural protein expressed from orf-206 of turnip yellow mosaic virus is proteolytically processed to produce n-terminal 150-kda and c-terminal 70-kda proteins. through the use of linker insertion and deletion analyses coupled to in vitro translation, we have delimited the protease domain to residues 731-885 encoded by the 150-kda coding region of orf-206. the effects of substitutions of conserved residues within this region were studied in two assays: a direct assay for proteolysis occ ... | 1994 | 8037790 |
| the role of the 3'-untranslated region of non-polyadenylated plant viral mrnas in regulating translational efficiency. | tobacco mosaic virus (tmv) is a positive-sense rna virus in which the single genomic rna functions as a messenger rna. it is a member of a class of plant viral rnas that are the only known non-polyadenylated mrnas in plants. the 3'-untranslated region (utr) of tmv genomic rna is the functional equivalent of a poly(a) tail in that it increases mrna stability and regulates translational efficiency. to determine whether the 3'-utr of other non-polyadenylated plant viral mrnas regulate translation, ... | 1994 | 8194747 |
| the tymv trna-like structure. | the genomic rna from turnip yellow mosaic virus presents a 3'-end functionally and structurally related to trnas. this report summarizes our knowledge about the peculiar structure of the trna-like domain and its interaction with trna specific proteins, like rnase p, trna nucleotidyl-transferase, aminoacyl-trna synthetases, and elongation factors. it discusses also the biological role of this structure in the viral life cycle. a brief survey of our knowledge of other trna mimicries in biological ... | 1993 | 8268257 |
| predicting rna h-type pseudoknots with the massively parallel genetic algorithm. | motivation: using the genetic algorithm (ga) for rna folding on a massively parallel supercomputer, maspar mp-2 with 16,384 processors, we successfully predicted the existence of h-type pseudoknots in several sequences. results: the ga is applied to folding the trna-like 3' end of turnip yellow mosaic virus (tymv) rna sequence with 82 nucleotides, the 3' utrs of satellite tobacco necrosis virus (stnv)-2 rna sequence with 619 nucleotides and stnv-i rna sequence with 622 nucleotides, and the bacte ... | 1997 | 9283762 |
| organization of turnip yellow mosaic virus investigated by neutron small angle scattering at 80 k: an intermediate state preceding decapsidation of the virion? | the organization of turnip yellow mosaic virus has been investigated by neutron small angle scattering at 300 k and 80 k in buffers containing various amounts of d2o. we confirm that in native virions, no substantial part of the rna is located at a radius larger than ca. 100-110 a, i.e., that there is very little interpretation of the rna into the capsid. at 80 k, scattering curves do not depend much upon contrast, from 40% d2o to 100% d2o buffers, but are strongly affected by interparticle inte ... | 1993 | 8272422 |
| in vitro transcripts of turnip yellow mosaic virus encompassing a long 3' extension or produced from a full-length cdna clone harbouring a 2 kb-long pcr-amplified segment are infectious. | two types of full-length cdna clones have been constructed corresponding to the entire genome of turnip yellow mosaic virus (tymv), from which infectious transcripts devoid of 5' non-viral extensions can be synthesized in vitro. the first type of transcript (ttyfl7) harbours 75 non-viral nucleotides at its 3' end, whereas the second type (ttyfl84) possesses only 2 non-viral nucleotides at its 3' end. the 2 kilobase-long 3' region of ttyfl84 derives from amplification by the polymerase chain reac ... | 1993 | 8284512 |
| transgenic plants that express genes including the 3' untranslated region of the turnip yellow mosaic virus (tymv) genome are partially protected against tymv infection. | in order to evaluate new possibilities for protecting plants against virus infection by interference with viral replication, two chimeric genes were constructed in which the (+) strand 3'-terminal 100 nucleotides (nt) of the noncoding region of the turnip yellow mosaic virus (tymv) genome were placed downstream from the sense or antisense cat coding region. the two chimeric genes were then introduced into the genome of rapeseed (brassica napus) using an agrobacterium rhizogenes vector system. pl ... | 1993 | 8294045 |
| cis-preferential replication of the turnip yellow mosaic virus rna genome. | the largest open reading frame of the turnip yellow mosaic virus rna genome encodes a 206-kda protein that is cleaved to yield n-terminal 150-kda (p150) and c-terminal 70-kda (p70) proteins. using a genomic cdna clone capable of generating infectious transcripts in vitro, we have introduced substitution, frameshift, and in-frame deletion mutations into the regions encoding both proteins. none of the mutant rnas was able to replicate independently in turnip protoplasts, indicating that p150 and p ... | 1993 | 8327488 |
| infectious eggplant mosaic tymovirus and ononis yellow mosaic tymovirus from cloned cdna. | eggplant mosaic virus (emv) and ononis yellow mosaic virus (oymv) are two tymoviruses that have ssrna genomes of about 6.2 kb and 6.3 kb, and which infect solanaceous and leguminous hosts, respectively. full-length cdna clones of these viruses were constructed with a t7 promoter adjacent to the 5' terminus of the dna copy of the viral genome, and with unique restriction endonuclease sites at the 3' terminus. this allowed rna to be transcribed from the dna encoding the genome. the transcript rna ... | 1993 | 8328917 |
| rna hybrid mismatch polymorphisms in australian populations of turnip yellow mosaic tymovirus. | in the mt. kosciusko alpine area of australia there are three well-separated populations of cardamine lilacina, an endemic sward-forming perennial brassica, and these are infected with turnip yellow mosaic tymovirus. the genetic variation in these viral populations has been assessed by an rna hybrid mismatch polymorphism method. about 100 isolates were examined; the genomic rna of each isolate was prepared from a shoot of a single wild c. lilacina plant. rna hybrid mismatch polymorphisms (rhmps) ... | 1993 | 8352660 |
| electrotransfection of turnip yellow mosaic virus rna into brassica leaf protoplasts and detection of viral rna products with a non-radioactive probe. | we describe here a convenient and efficient system for studying turnip yellow mosaic virus (tymv) replication in leaf protoplasts. inoculation of rapeseed (brassica napus) or chinese cabbage (b. sinensis) protoplasts was achieved via electroporation, and sensitive detection of viral rna products was performed by northern blot analyses using a non-radioactive digoxigenin-labelled cdna probe. virus replication was detected when 1.5 x 10(6) rapeseed protoplasts were inoculated with 20 ng of tymv rn ... | 1993 | 8376966 |
| in vitro transcription of rnas with defined 3' termini from pcr-generated templates. | we demonstrate the feasibility of using pcr to economically amplify sufficient template to permit the transcription by t7 rna polymerase of preparative amounts of rnas for biochemical analyses. we show that a standard 100-microliter pcr amplification of a fragment from the 3' end of the genomic cdna of turnip yellow mosaic virus yields enough template to support the synthesis of about 50 micrograms of a 264-nucleotide-long transcript. the choice of the 3' primer defines the 3' terminus of the tr ... | 1993 | 8424878 |
| identification of the cleavage site recognized by the turnip yellow mosaic virus protease. | the noncapsid protein expressed from orf-206 of turnip yellow mosaic virus (tymv) is autocatalytically processed by a papain-like protease, producing n-terminal 150-kda and c-terminal 70-kda proteins. by introducing two methionine residues near the n-terminus of the 70-kda protein, we have obtained n-terminal amino acid sequence of that protein produced from [35s]methionine-labeled in vitro translations. the introduction of methionine residues was demonstrated to not interfere with viral replica ... | 1996 | 8599230 |
| expression of the 69k movement protein of turnip yellow mosaic virus in insect cells. | the nonstructural 69-kilodalton (k) protein of turnip yellow mosaic virus is necessary for systemic spread of the virus within the plant. to examine the behavior of the 69k protein in vivo, antibodies were raised against the carboxy-terminal region of this protein. the full-length 69k protein was also expressed in insect cells using a recombinant baculovirus. studies on the posttranslational modifications of the 69k protein in insect cells revealed that the protein is phosphorylated but not glyc ... | 1996 | 8623539 |
| do light-induced ph changes within the chloroplast drive turnip yellow mosaic virus assembly? | turnip yellow mosaic virus (tymv) induces gross morphological and biochemical changes in the chloroplasts of infected cells. viral rna is synthesized in vesicles formed by invagination of the outer chloroplast bilayer. virion assembly occurs at the neck of these vesicles and requires illumination. data collected over the last three decades are consistent with the hypothesis that light-induced generation of a low ph drives tymv assembly within the intermembrane space of chloroplasts. in a low-ph ... | 1996 | 8627217 |
| the turnip yellow mosaic virus trna-like structure cannot be replaced by generic trna-like elements or by heterologous 3' untranslated regions known to enhance mrna expression and stability. | the trna-like structure (tls) at the 3' end of the turnip yellow mosaic virus genome was replaced with heterologous trna-like elements, and with a poly(a) tail, in order to assess its role. replacement with the valylatable tlss from two closely related tymoviruses resulted in infectious viruses. in contrast, no systemic symptoms on plants, and only low viral accumulations in protoplasts, were observed for three chimeric genomes with 3' sequences known to enhance mrna stability and translatabilit ... | 1996 | 8642631 |
| difference imaging reveals ordered regions of rna in turnip yellow mosaic virus. | turnip yellow mosaic virus (tymv) is a small icosahedral plant virus with a capsid containing 180 subunits arranged with hexamer-pentamer clustering. cross-linking studies have indicated extensive contacts between rna and coat protein, suggesting that substantial parts of the rna might be icosahedrally ordered. | 1996 | 8740361 |
| protein and virus crystal growth on international microgravity laboratory-2. | two t = 1 and one t = 3 plant viruses, along with a protein, were crystallized in microgravity during the international microgravity laboratory-2 (iml-2) mission in july of 1994. the method used was liquid-liquid diffusion in the european space agency's advanced protein crystallization facility (apcf). distinctive alterations in the habits of turnip yellow mosaic virus (tymv) crystals and hexagonal canavalin crystals were observed. crystals of cubic satellite tobacco mosaic virus (stmv) more tha ... | 1995 | 7669890 |