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.

Effect of leukocyte antibodies and HLA matching on the intravascular recovery, survival, and tissue localization of 111-indium granulocytes

The effect of leukocyte antibodies detected under different conditions on the fate in vivo of granulocytes was studied using 111-indium-labeled granulocytes. Sera from patients were tested by granulocyte agglutination (GA), granulocytotoxicity (GC), granulocyte immunofluorescence (GIF), lymphocytotoxicity (LC), and antibody-dependent lymphocyte-mediated granulocytotoxicity. Granulocytes from donors to be studied were labeled with 111-indium and injected. Then the intravascular recovery and survival or tissue localization was determined in 93 studies. Antibodies detected by granulocyte agglutination were associated with a significant reduction in recovery (6.7% v 30.8% in controls; P less than .001) and t1/2 (0.3 hours v 5.6 hours in controls; P = .002). When all possible combinations of serum reactivity were considered, reactivity in the GA plus GIF assays had the best correlation with decreased recovery (R2 = .49; P less than .001) and t1/2 (R2 = .73; P less than .001). When the relationship between the strength of antibody reactivity and the recovery and t1/2 were analyzed, the best relationship was between the combination of LC and GIF with recovery (R2 = .62; P = .001). Because of the general availability of the HLA (LC) testing, the role of LC reactivity was investigated in other ways. There was a strong relationship between sera highly reactive by LC and those reactive by GIF. These highly reactive sera were also associated with reduced recovery and t1/2. The influence of specific HLA antigen mismatches was also studied. When donor and recipient were mismatched for the HLA-A2, B8, or BW44 antigens, there was a significant reduction in either recovery, t1/2, or both. Tissue localization was studied by body scans in patients with and without known sites of inflammation. Antibodies detected by a combination of GA and GIF caused abnormal pulmonary sequestration of granulocytes (three cases) and failure of granulocytes to localize at known sites of inflammation (three cases). HLA (LC) antibodies did not alter tissue localization despite the presence of the corresponding HLA antigens on granulocytes. It appears that GA, GIF, or a combination of these tests is the most effective predictor of altered in vivo fate of granulocytes. However, sera highly reactive by LC and GIF probably define a group of highly immunized patients in whom granulocyte recovery and t1/2 are also reduced. Mismatching for certain HLA antigens is also associated with reduced granulocyte recovery and survival. At present, GA, with or without the immunofluorescence assay, is the most effective predictor of altered in vivo granulocyte activity.(ABSTRACT TRUNCATED AT 400 WORDS)

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.

Recombination between mutant cauliflower mosaic virus DNAs

A class of mutants of cauliflower mosaic virus (CaMV) DNA was distinguished based on its members' ability to induce symptoms when coinoculated on plants with other CaMV DNAs mutant at a different locus. Three mutants, one each in open reading frame I, III, and VI had this ability. A second class of mutant DNAs did not induce symptoms unless combined with a mutant DNA of the first class. Viral DNA extracted from diseased plants was shown by restriction enzyme digestion to have lost the mutant alleles. When turnip plants were inoculated with a recombining mutant derived from DNA of the Cabbage S isolate and a mutant derived from DNA of a different isolate, a heterogeneity in the viral DNA extracted from the diseased plants was detected by restriction enzyme analysis. Restriction analysis of cloned representatives of this heterogeneous population revealed regions consistent with repair of heteroduplexes formed during general recombination between duplex DNAs. Some regions consistent with this mechanism or with recombination by strandswitching during reverse transcription were found.

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.

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.

Antibody-dependent lymphocyte-mediated granulocytotoxicity (ADLG) for the detection of granulocyte antibodies

An antibody-dependent cell-mediated granulocytotoxic assay (ADLG) has been developed to detect antibodies to human granulocytes. This study examines some possible variables in this assay, the ADLG activity in serum from normal individuals, the contribution of ABO isohemagglutinins and the sensitivity and specificity of this technique. Significant differences in percentage cytotoxicity of ABO compatible and incompatible cell/serum combinations were detected in the normal population. Human serum with antibodies to the neutrophil specific antigens NA1 and NB1 gave positive results in the ADLG assay. However, differences in sensitivity and specificity were observed among various sera. ADLG activity was dependent on the source of effector cells. Effector and target cells stored in vitro were unsatisfactory in this assay. The ADLG assay may be a valuable addition to existing granulocyte serological methods and provide useful clinical information on mechanisms of immune neutropenias.

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.

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.

Nucleotide sequence at the 5' extremity of tobacco-mosaic-virus RNA. 2. The coding region (nucleotides 69-236)

In the preceding paper it was shown that the first A-U-G codon in tobacco mosaic virus RNA is separated from the 5' terminus by a sequence of 68 nucleotides devoid of internal guanosine residues. In this paper we present the sequence of 165 residues immediately following the first potential initiation codon. The characterized sequence contains four nonsense codons but none are in phase with the prospective initiation codon. Several lines of evidence, including direct characterization of the portion of the RNA molecule which binds to and is protected by the ribosome in the course of initiation, all support the idea that the A-U-G at position 69-71 is a functional initiation signal for viral protein synthesis.

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.

Nucleotide sequence (n=159) of the amino-acid-accepting 3'-OH extremity of turnip-yellow-mosaic-virus RNA and the last portion of its coat-protein cistron

The experiments described in this paper and the following one establish the sequence of the 3'-OH terminal 159 nucleotides of turnip yellow mosaic virus RNA. Uniformly 32P-labeled turnip yellow mosaic virus RNA was partially digested with T1 ribonuclease and the fragments were fractionated by polyacrylamide gel electrophoresis. Fragments originating from the 3'-OH end of the RNA molecule were identified by testing for the 3'-terminal oligonucleotide, C-COH, after total U2 ribonuclease hydrolysis. Once identified, the 3'-OH terminal fragments were sequenced by the methods of Sanger et al. The first 51 nucleotides of the longest of the sequenced fragments (158 nucleotides) extends into the 3'-terminal part of the coat protein cistron. The coat protein cistron is followed by a stretch of 108 untranslated nucleotides whose function, though still unknown, is probably linked to the tRNA-like properties which have been attributed to the 3'-OH extremity of this viral RNA. Two possible secondary structures are proposed for the sequence and the implications of the findings with regard to the tRNA-like properties of the extremity are discussed.

Improved technic for canine lung transplantation

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Mechanism and prevention of fixed high vascular resistance in autografted and allografted lungs

The fixed vascular resistance observed in tranisplanted Ilunlgs and attriblted to denervation can be avoided by angioplastic wideniing of the pulmonary artery anastotosis. With distenisible arterial anrastomoses, aultografted an, d allografted Ilunzgs vasodilate niormzally with inicreased flow and cani sutstaini dogs whose contralateral pulmonary artery is ligated imumediately after lutng transplanitation.