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H Guilley

Publications and source records attributed to H Guilley.

At least 55 records · Page 3Linked to original sources
PubMed1990

Multiplication of beet necrotic yellow vein virus RNA 3 lacking a 3' poly(A) tail is accompanied by reappearance of the poly(A) tail and a novel short U-rich tract preceding it.

Beet necrotic yellow vein virus RNAs 1 and 2 but not RNAs 3 and 4 are required for viral multiplication in Chenopodium quinoa leaves. Elimination of the 3' poly(A) tail from RNA 3 transcripts markedly attenuated their ability to be amplified when co-inoculated with RNAs 1 and 2 to this host. Successful multiplication of the tailless RNA 3 was accompanied by the reappearance of new 3' poly(A) tails on the progeny. The evidence suggests that the newly acquired poly(A) sequence results from the action of a poly(A) polymerase rather than recombination with the homologous 3' terminal domains of RNAs 1 or 2. An unexpected feature of these progeny RNA 3 molecules was the presence of a novel short heterogenous U-rich tract separating the poly(A) tail from the 3' end of the heteropolymeric RNA 3 sequence proper.

Base Composition↗
PubMed1989

In vitro synthesis of biologically active beet necrotic yellow vein virus RNA.

Beet necrotic yellow vein virus (BNYVV) has a quadripartite plus-strand RNA genome in which the two smallest genome components, RNA 3 and 4, are not necessary for virus multiplication in leaves. Infectious transcripts of BNYVV RNA 3 and 4 have already been described (V. Ziegler-Graff, S. Bouzoubaa, I. Jupin, H. Guilley, G. Jonard, and K. Richards (1988) J. Gen. Virol. 69, 2347-2357). In this paper we describe synthesis of a full-length RNA-1 transcript by bacteriophage T7 RNA polymerase-directed run-off transcription of cloned viral cDNA. A recombinant plasmid containing a full-length cDNA insert of RNA 2 could not be maintained in Escherichia coli. Therefore full-length transcript of RNA 2 was produced by transcription of cDNA ligation products without amplification in bacteria. When inoculated together to leaves of Chenopodium quinoa or Tetragonia expansa the RNA 1 and 2 transcripts were infectious; they also supported multiplication of the BNYVV RNA 3 and 4 transcripts, providing a totally synthetic inoculum of the virus. In one recombinant clone of RNA 2 a point mutation causing an arginine to serine substitution at position 119 of the viral coat protein was discovered. The mutation was detected because the resulting coat protein had altered electrophoretic mobility. RNA 2 transcripts containing this mutation were infectious but viral RNA was not encapsidated. The mutation also interfered with long distance movement of the virus in spinach, presumably as a consequence of the packaging deficiency.

Capsid↗
PubMed1988

Nucleotide sequence of beet western yellows virus RNA.

The nucleotide sequence of the genomic RNA (5641 nt) of beet western yellow virus (BWYV) isolated from lettuce has been determined and its genetic organization deduced. The sequence of the 3'terminal 2208 nt of RNA of a second BWYV isolate, obtained from sugarbeet, was also determined and was found to be very similar but not identical to that of the lettuce isolate. The complete sequence of BWYV RNA contains six long open reading frames (ORFs). A cluster of three of these ORFs, including the coat protein cistron, display extensive amino acid sequence homology with corresponding ORFs of a second luteovirus, the PAV isolate of barley yellow dwarf virus (BYDV) (1,2). The ORF corresponding to the putative viral RNA-dependant RNA polymerase, on the other hand, resembles that of southern bean mosaic virus. There is circumstantial evidence that expression of the BWYV RNA polymerase ORF may involve a translational frameshift mechanism. The ORF immediately following the coat protein cistron may be translated by in-frame readthrough of the coat protein cistron amber termination codon. Similar mechanisms have been proposed for expression of the corresponding ORFs of BYDV(PAV) (1).

Amino Acid Sequence↗
PubMed1988

Effect of beet necrotic yellow vein virus RNA composition on transmission by Polymyxa betae.

Beet necrotic yellow vein virus (BNYVV) is naturally transmitted by the soil-borne fungus Polymyxa betae and usually remains confined to the roots of infected sugarbeets. In naturally infected sugarbeets the virion RNA always consists of four components which are uniform in size in different isolates but when BNYVV is propagated by mechanical inoculation to leaves of Chenopodium quinoa the two smallest RNA components, RNA-3 and -4, may undergo deletion or disappear from the isolate, suggesting that they are only essential for the natural mode of infection. To test this hypothesis, several C. quinoa isolates of BNYVV with different RNA-3 and -4 contents have been retransmitted to sugarbeet root via P. betae. The results show that the two isolates containing no detectable full-length RNA-3 and -4 are poorly transmitted and that cases of successful infection are associated with the reappearance of full-length RNA-3 and -4.

Fungi↗
PubMed1985

Nucleotide sequence and genome organization of carnation mottle virus RNA.

The complete nucleotide sequence of carnation mottle genomic RNA (4003 nucleotides) is presented. The sequence was determined for cloned cDNA copies of viral RNA containing over 99% of the sequence and was completed by direct sequence analysis of RNA and cDNA transcripts. The sequence contains two long open reading frames which together can account for observed translation products. One translation product would arise by suppression of an amber termination codon and the sequence raises the possibility that a second suppression event could also occur. Sequence homology exists between a portion of the carnation mottle virus sequence and that of putative RNA polymerases from other RNA viruses.

Amino Acid Sequence↗
PubMed1985

Chimeric vector construction for higher-plant transformation.

A chimeric vector pKR612B1 was developed containing the neomycin phosphotransferase (APH) gene from the Tn5 transposon under the control of the gene VI promoter of cauliflower mosaic virus (CaMV), and was used to transform higher plant protoplasts. Plasmid pDOB612, the parental vector of pKR612B1, has two unique restriction sites, SmaI and BamHI, positioned just downstream of the CaMV gene VI promoter sequence. These unique cloning sites can be used for any kind of gene insertion into this vector. Using the polyethylene glycol transformation procedure, a large number of turnip and tobacco protoplasts were transformed and proved to be resistant to kanamycin (Km). From tobacco protoplasts whole Km-resistant plants were regenerated and shown to contain the integrated foreign gene. APH activity was detected in both transformed calli and in regenerated plants. DNA from transformed clones was analysed by Southern blot hybridization, showing the presence of the Tn5-derived gene.

Chimera↗
PubMed1985

Immunological detection of cauliflower mosaic virus gene V protein produced in engineered bacteria or infected plants.

Antiserum was prepared against a synthetic peptide corresponding to the C-terminal 25 amino acids (aa) of the protein encoded by cauliflower mosaic virus (CaMV) gene V, which is thought to be a reverse transcriptase involved in viral DNA replication. This antiserum was used to detect the expression of CaMV gene V either in Escherichia coli JM103 transformed by an expression vector containing CaMV gene V or in CaMV-infected plants. In both cases, an 80-kDal protein has been detected.

Amino Acid Sequence↗
PubMed1983

Observations concerning the discontinuous DNAs of cauliflower mosaic virus.

The double-stranded circular DNA encapsidated within cauliflower mosaic virus (CaMV) particles contains three single-stranded discontinuities, two in one strand and one in the other, so that, upon denaturation, three linear single-stranded DNAs are produced. Here we show that a fourth much smaller single-stranded DNA, termed alpha1, is also present in denatured CaMV DNA preparations. The 5' extremity of alpha1 is identical to that of the alpha-strand, the strand of DNA possessing only one interruption, while its 3' extremity lies just two nucleotides downstream from a major transcription initiation site. We also show that the interrupted strand at each discontinuity sometimes has a single ribonucleotide in place of a deoxyribonucleotide at its 5' extremity. Oligoribonucleotide chains of eight and 10 residues in length have also been detected at the 5' end of one of the discontinuities. These structures are thought to be the vestiges of primers which have not been completely excised prior to encapsidation of the DNA. The possibility that synthesis of the alpha-strand occurs by reverse transcription of viral RNA using initiator tRNA(met) as primer is discussed.

Caulimovirus↗
PubMed1982

Transcription of Cauliflower mosaic virus DNA: detection of promoter sequences, and characterization of transcripts.

Four RNA transcripts encoded by cauliflower mosaic virus DNA have been detected in the polyadenylated RNA from virus-infected turnip leaves. Two of these transcripts, the major 35S and the 8S species, have the same 5' termini, at nucleotide 7435. A viral DNA fragment encompassing this region directs transcription initiation at this point in vitro. The 5' terminus of the 19S transcript is at nucleotide 5764, and a corresponding viral DNA fragment also directs transcription initiation in vitro. The major 35S RNA is a complete transcript of the circular viral genome, and is 3'-coterminal with 19S RNA at nucleotide 7615. The 8S RNA has its 3' extremity at delta 1, the single-stranded interruption in the transcribed strand of virion DNA. A minor 35S RNA has also been detected that has its 5' and 3' termini at delta 1.

Base Sequence↗
PubMed1982

Nucleotide sequence of DNA from an altered-virulence isolate D/H of the cauliflower mosaic virus.

The double-stranded DNA from the isolate D/H with an altered virulence of the cauliflower mosaic virus (CaMV) contains 8016 bp. The DNA is circular and possesses, like the DNA of most CaMV strains, three sequence interruptions. The comparison of its sequence with the previously published sequences of two other CaMV strains (Cabb-S and CM 1841) leads to the following conclusions: (1) The genetic organization of all three CaMV strains is identical with six potential genes (open reading frames) and two intergenic regions; (2) considered pairwise, the three DNAs differ from one another by only about 5% with base substitutions accounting for most of the changes although several deletions and insertions are also observed. The sequence differences among the three strains are spread in a uniform manner upon the genome except for the two intergenic regions, which are more highly conserved. The stability of the noncoding regions is probably linked to the fact that they carry sequences important for the initiation and termination of transcription. On the other hand, the sequence variation in the open reading frames has relatively little effect on the sequence of the corresponding polypeptides as changes occur preferentially in the third position of the reading frame triplets. It is anticipated that knowledge of the DNA sequences of several CaMV strains will facilitate construction of inter-strain recombinants which, once available, can be used to correlate gene structure and function.

Base Composition↗
PubMed1980

Nucleotide sequence of cauliflower mosaic virus DNA.

The complete nucleotide sequence (8024 nucleotides) of the circular double-stranded DNA of cauliflower mosaic virus has been established. The DNA molecule is known to possess three discrete single-stranded discontinuities, often referred to as "gaps," two in one strand and one in the other. The sequence data indicate that gap 1, the single discontinuity in the alpha strand, corresponds to the absence of no more than one or two nucleotides with respect to the complementary beta strand. The two discontinuities in the beta strand, however, are not authentic gaps since no nucleotides are missing, but are instead regions of sequence overlap: a short sequence (19 residues for gap 2, t least 2 residues for gap 3) at one terminus of each discontinuity, probably the 5' terminus, is displaced from the double helix by an identical sequence at the other boundary of the discontinuity. Analysis of the distribution of nonsense codons in the DNA sequence is consistent with other evidence that only the alpha strand is transcribed. The coding region extends around the circular molecule from 4 map units of gap 1, the map origin, to map position 91, and consists of six long open reading frames. Our findings suggest, but do not prove, that the DNA sequence of the open reading frames is colinear with viral protein sequences. The cistron for the viral coat protein, which is probably synthesized in the form of a precursor, has been situated in coding region IV on the basis of its unusual amino acid composition.

Amino Acid Sequence↗
PubMed1979

Sequence of 1000 nucleotides at the 3' end of tobacco mosaic virus RNA.

The sequence of 1000 nucleotides at the 3' end of tobacco mosaic virus RNA has been determined. The sequence contains the entire coat protein cistron as well as regions to its left and right. Sequence characterization was by conventional methods for use with uniformly 32P labeled RNA complemented by newer methods for in vitro 5' and 3' 32P end-labeling of RNA and its subsequent rapid analysis. The noncoding region separating the coat protein cistron from the 3' terminus is 204 residues long and may be folded into a clover-leaf-type secondary structure. The distribution of termination codons to the left of the coat protein cistron suggests that the end of the adjacent cistron is separated from the beginning of the coat protein cistron by only two nucleotides. The subgenomic viral coat protein mRNA was isolated from infected tissue and shown to be capped. The nontranslated sequence separating the cap from the AUG initiation codon is 9 residues long and thus overlaps a portion of the adjacent cistron on the genome RNA.

Base Sequence↗
PubMed1978

Nucleotide sequence at the 5' extremity of tobacco-mosaic-virus RNA. 1. The noncoding region (nucleotides 1-68).

The sequence of the 5' noncoding region of tobacco mosaic virus RNA has been determined. The noncoding region is 68 nucleotides long and is unusual in that it contains no internal guanosine residues. The long T1 oligonucleotide containing the guanosine-free tract was isolated from a T1 ribonuclease digest of tobacco mosaic virus RNA and sequenced by labelling techniques in vitro using polynucleotide kinase. The guanosine-free tract is terminated by the first potential initiation codon in the RNA molecule and several lines of evidence suggest that this AUG triplet is operational in initiating viral protein synthesis (see following paper). The 5'-noncoding region cannot base-pair extensively with the 3'-terminal sequence of 18-S ribosomal RNA from rabbit reticulocytes.

Base Sequence↗
PubMed1978

Nucleotide sequence of turnip yellow mosaic virus coat protein mRNA.

The primary structure of the coat protein messenger RNA of turnip yellow mosaic virus is presented. This sequence is the first complete nucleotide sequence of the coat protein messenger of a plant virus to be reported. The coding region, consisting of 567 nucleotides, is flanked by a 5' noncoding region of 19 nucleotides (not including the initiation codon and the cap structure) and by a 3' noncoding region of 109 nucleotides (including the termination signal). The coat protein mRNA has a base composition identical to that of the genome RNA with, in particular, the same high content in cytosine (38%). The codons that govern the incorporation of amino acids into the coat protein are nonrandomly utilized: is greater than 50% of the time the third base of the codons used is a cytosine. This pattern of codon preference is particularly marked for Leu, lle Val, Thr and Cys.

Base Sequence↗
PubMed1978

Nucleotide sequence at the 5' extremity of turnip yellow mosaic virus genome RNA.

The sequence of the first 110 nucleotides at the 5' extremity of turnip yellow mosaic virus genome RNA has been determined. The sequence is blocked at its 5' terminus with the group pppm(7)G and contains two AUG triplets. The determined sequence bears a strong resemblance to the 5' noncoding region of rabbit beta-globin mRNA. Region 95-103 of the sequence can base-pair with part of the 3' extremity of either the genome RNA or the coat protein mRNA.

Journal Article↗
PubMed1978

The nucleoside sequence of tyrosine tRNA from Bacillus stearothermophilus.

The nucleotide sequence of tRNATyr from B. stearothermophilus has been determined: pG-G-A-G-G-G-G-s4U-A-G-C-G-A-A-G-U-Gm-G-C-U-A-A-m1A-C-G-C-G-G-C-G-G-A-C-U-Q-U-A-ms2i6A-A-psi-C-C-G-C-U-C-C-C-U-U-U-G-G-G-U-U-C-G-G-C-G-G-T-psi-C-G-A-A-U-C-C-G-U-C-C-C-C-C-U-C-C-A-C-C-AOH. A combination of classical fingerprinting methods, partial nuclease P1 digestion and two-dimensional homochromatography and a rapid "read off" sequencing gel technique were used to establish the complete nucleotide sequence.

Base Sequence↗