| immunity to transmissible (coronaviral) enteritis of turkeys (bluecomb). | turkey flocks recovering from natural and laboratory induced coronaviral enteritis developed lifelong immunity. virus neutralization tests indicated that neutralization capacity of serums from recovered turkeys was low. one-way cross challenge test using turkeys inoculated with various bluecomb isolates revealed close antigenic relationship or antigenic identity among bluecomb isolates. the controlled application of intestinal preparations containing coronavirus as a vaccination procedure had va ... | 1975 | 164801 |
| comments on the etiology and immunity of transmissible (coronaviral) enteritis of turkeys (bluecomb). | | 1975 | 164802 |
| detection of turkey coronaviral enteritis (bluecomb) in field epiornithics, using the direct and indirect fluorescent antibody tests. | in minnesota, efforts have been made over the past 10 years to eliminate turkey coronaviral enteritis (tce, bluecomb) by controlled depopulation and decontamination with a rest period before restocking. in 1973, clinical observations indicated that bluecomb was restricted to one limited area in minnesota. five epiornithics occurred during late 1973 and 1974, involving 5 different farms in this limited geographic area. during 1975, 3 epiornithics of tce were investigated, involving 185,000 turkey ... | 1977 | 200156 |
| secretory antibodies against turkey coronaviral enteritis. | studies on local immunity to transmissible coronaviral enteritis of turkeys (bluecomb) was made. intestinal secretions and bile from affected birds contained secretory immunoglobulins against coronaviral antigen throughout the 6 months' duration of the experiment. attempts to purify and to characterize the globulins in intestinal secretions and bile of the affected birds were made, using the techniques of gel filtration, deae chromatography, and immunoelectrophoresis. class-specific anti-turkey ... | 1978 | 211889 |
| the sizes of rna subunits isolated from high and low leukaemogenic friend virus. | the sizes of non-covalently linked rna subunits isolated from highly leukaemogenic friend virus derived from the plasma (pv, plasma virus) of leukaemic mice were compared to the rna subunits isolated from low leukaemogenic friend virus grown in tissue culture (tcv, tissue culture virus). histograms derived from electron microscope measurements showed that about one-half of the plasma virus rna was 1.4 to 2.5 micron in length, corresponding to a mol. wt. range from 1.8 x 10(6) to 3.2 x 10(6) and ... | 1978 | 660164 |
| a quantitative comparison between in vivo-and in vitro-derived friend leukemia virus. | the biological activities of rna viruses derived from friend leukemia cells in culture (tcv) were compared with those of viruses derived from the plasma (pv) of mice infected with friend leukemia virus (flv). the comparison was quantitatively based on the actual number of viruses used in each experiment as determined by counting under the electron microscope. electron microscopy also provided a qualitative assessment of the structural integrity of the concentrated virus particles used in various ... | 1975 | 1184245 |
| single amino acid change in the helicase domain of the putative rna replicase of turnip crinkle virus alters symptom intensification by virulent satellites. | the virulent satellite [satellite c (sat c)] of turnip crinkle virus (tcv) is a small pathogenic rna that intensifies symptoms in tcv-infected turnip plants (brassica campestris). the virulence of sat c is determined by properties of the satellite itself and is influenced by the helper virus. symptoms produced in infections with sat c differ in severity depending on the helper virus. the tcv-ji helper virus produces more severe symptoms than the tcv-b helper virus when inoculated with sat c. to ... | 1992 | 1370351 |
| genomic relationship between turkey and bovine enteric coronaviruses identified by hybridization with bcv or tcv specific cdna probes. | genomic relationships between turkey and bovine coronavirus (tcv and bcv), which are currently placed in distinct antigenic groups, were demonstrated by hybridization using specific cdna probes. bcv-specific recombinant plasmid probes p 52, p 27, and p 247, holding inserts derived from (probably nonstructural) genes, and plasmids pn 17 and pn 9 holding the n and m gene, respectively, permitted the detection of isolates of both bcv and tcv with similar sensitivities. similarly, probing supernatan ... | 1991 | 1662038 |
| hemorrhagic enteritis of turkeys. | hemorrhagic enteritis (he), an economically important disease of turkeys is caused by a type ii adenovirus. the virus is ubiquitous and is liable to infect most field turkeys. in unprotected turkey flocks, infection with virulent hemorrhagic enteritis virus (hev) may result in variable mortality and immunodepression. turkeys younger than 2-4 weeks of age are resistant to clinical he. this age-related resistance is expressed in the presence or absence of maternal antibodies against hev. clinical ... | 1991 | 1664163 |
| transmissible enteritis of turkeys: experimental inoculation studies with tissue-culture-adapted turkey and bovine coronaviruses. | four quebec isolates of turkey enteric coronaviruses (tcvs) and three isolates of bovine enteric coronaviruses (bcvs) were serially propagated in hrt-18 and compared for their pathogenicity in turkey embryos and turkey poults. by immunoelectron microscopy, hemagglutination-inhibition, and western immunoblotting assays, tissue-culture-adapted quebec tcv isolates were found to be closely related to the reference minnesota strain of tcv and the mebus strain of bcv. genomic relationships between tcv ... | 1991 | 1664719 |
| recombination between satellite rnas of turnip crinkle virus. | turnip crinkle virus (tcv) is associated with satellite (sat) rnas (sat-rna d, sat-rna f), defective interfering (di) rnas (di rna g, di1 rna), and one rna with properties of both sat-rnas and di rnas (sat-rna c). when plants were inoculated with tcv, sat-rna d and in vitro sat-rna c transcripts containing non-viable mutations in the 5' domain, recombinant sat-rnas were recovered. these recombinants were composed of sat-rna d at the 5' end and sat-rna c sequences at the 3' end. analysis of 20 in ... | 1990 | 1693330 |
| nonmutant forms of the avirulent satellite d of turnip crinkle virus are produced following inoculation of plants with mutant forms synthesized in vitro. | the avirulent satellite rna d (sat d) of turnip crinkle virus (tcv) has been cloned as a copy dna. rna transcripts synthesized in vitro from the cloned cdna are infectious when coinoculated with rna transcripts of the cloned tcv genome. sat d is the smallest and most likely the progenitor of the other tcv satellites and, in contrast to the virulent satellite rna c (sat c), does not intensify viral symptoms. mutant forms of sat d including internal deletions up to 50 bases yielded sat d in infect ... | 1991 | 1711258 |
| mutations in a satellite rna of turnip crinkle virus result in addition of poly(u) in vivo. | turnip crinkle virus (tcv) is associated with many subviral rnas including satellite (sat-) rnas which require a helper virus for infectivity. when plants were inoculated with tcv and transcripts of tcv sat-rna c containing deletions of 3 to 8 nucleotides beginning at position 100 and extending toward the 5' end, some of the sat-rna isolated from plants migrated more slowly than expected on denaturing polyacrylamide gels. cleavage of the sat-rna into two segments by digestion with rnase h follow ... | 1991 | 1713000 |
| characterization and location of the structural polypeptides of turkey enteric coronavirus using monoclonal antibodies and enzymatic treatments. | | 1990 | 1715664 |
| recombination between satellite and genomic rnas of turnip crinkle virus. | new recombinant molecules formed from satellite and genomic rnas of turnip crinkle virus (tcv) have been characterized. known collectively as sat-rna cx, these molecules are composed of a nearly full-length segment of a previously characterized tcv satellite rna (sat-rna d) at the 5' end joined to variable lengths of tcv genomic rna 3' terminal sequence. sat-rna cx molecules fall into two classes: molecules of 420 to 435 bases and larger species of 501 to 506 bases. the tcv sequence at the junct ... | 1991 | 1716029 |
| turnip crinkle virus genes required for rna replication and virus movement. | we have used infectious in vitro transcripts from mutagenized turnip crinkle virus (tcv) cdna clones to identify the gene products required for viral rna replication, virion assembly, and intercellular movement. previous sequence analysis of the tcv genome revealed the presence of five open reading frames which had the potential to encode gene products of 88, 38, 28, 9, and 8 kda. inoculation of protoplasts with infectious rna revealed that only the p28 and p88 gene products are required for vir ... | 1992 | 1727594 |
| sequence analysis of the turkey enteric coronavirus nucleocapsid and membrane protein genes: a close genomic relationship with bovine coronavirus. | the 3' end of the turkey coronavirus (tcv) genome and the gene encoding the nucleocapsid protein (n) were cloned and sequenced. the gene encoding the membrane protein (m) was obtained by cloning a polymerase chain reaction (pcr)-amplified fragment obtained using bovine coronavirus (bcv)-specific primers. furthermore, five tcv dna fragments, obtained by pcr on rna from clinical specimens and corresponding to either the n terminus of the m protein or the complete m protein were also cloned and seq ... | 1991 | 1856695 |
| haemorrhagic enteritis of turkeys. | | 1990 | 1964777 |
| evidence of close relatedness between turkey and bovine coronaviruses. | | 1990 | 1966438 |
| point mutations in the turnip crinkle virus capsid protein affect the symptoms expressed by nicotiana benthamiana. | in an effort to determine the biological function(s) of the capsid protein protruding domains unique to the plant carmo- and tombusviruses, we constructed turnip crinkle virus (tcv) mutants in which tandem, in-frame translation terminators replaced the first two codons of the five-amino acid hinge between the shell and the protruding domains of the tcv capsid protein. one of the mutants replicated in inoculated leaves and protoplasts without detectable accumulation of capsid protein. the mutant ... | 1991 | 2053278 |
| antigenic and genomic relationships among turkey and bovine enteric coronaviruses. | antigenic and genomic relationships among tissue culture-adapted turkey enteric coronavirus (tcv) isolates, three strains of avian infectious bronchitis virus (ibv), and mammalian coronaviruses were investigated. immunoblotting and immunoprecipitation experiments using polyclonal antisera showed that the four major structural proteins of tcv cross-reacted with the four homologous proteins of bovine enteric coronavirus (bcv), the n and m proteins of mouse hepatitis virus serotype 3, and the n pro ... | 1990 | 2159566 |
| genome structure of tobacco necrosis virus strain a. | an almost complete sequence of the rna genome of tobacco necrosis virus (tnv) strain a has been determined. the genome organization is very similar to that of carnation mottle virus (carmv) and turnip crinkle virus (tcv). the 5'-proximal open reading frame (orf) encodes a 23-kda protein and read-through of its amber codon into the second orf is presumably used for the translation of a 82-kda protein. the third large orf encodes the 30-kda coat protein. two small orfs are located upstream and one ... | 1990 | 2371773 |
| characterization of group ii avian adenoviruses with a panel of monoclonal antibodies. | the interaction between a panel of ten monoclonal antibodies and hemorrhagic enteritis virus, a group ii avian adenovirus, was determined. the monoclonal antibodies reacted with all nine isolates of group ii avian adenoviruses, but not with any of five types of group i avian adenoviruses. all ten monoclonal antibodies recognized antigenic determinants on the hexon protein of hemorrhagic enteritis virus when analyzed by immunoprecipitation and immunoblotting. they reacted only with the native hex ... | 1988 | 2461793 |
| detection of turnip crinkle virus on agarose gel electropherograms at the nanogram load level. | the previous conditions for the physical characterization of turnip crinkle virus (tcv) by quantitative agarose gel electrophoresis [1, 2] were limiting the method to the microgram load level and were therefore insufficiently sensitive to satisfy the need in many areas of virology for detection of viruses containing single-stranded rna at the nanogram level. the present report remedies that defect by presenting a technique compatible with the nanogram load level of such viruses. the technique is ... | 1988 | 2466661 |
| antigenic and polypeptide structure of turkey enteric coronaviruses as defined by monoclonal antibodies. | twenty-nine hybridoma cells lines, producing monoclonal antibodies (mabs) to the minnesota strain of turkey enteric coronavirus (tcv), have been established by fusion of sp2/0 myeloma cells with spleen cells from balb/c mice immunized with purified preparations of the egg-adapted or tissue culture-adapted virus. the hybridomas produced mainly igg2a or igg1 antibodies. western immunoblotting experiments with purified virus, and immunoprecipitation tests with [35s]methionine-labelled infected cell ... | 1989 | 2472464 |
| detection of turkey enteric coronavirus by enzyme-linked immunosorbent assay and differentiation from other coronaviruses. | a double-antibody elisa for the detection of coronaviruses in intestinal contents from turkey poults with diarrhea was developed. antibodies were raised in rabbits and guinea pigs against a minnesota isolate of turkey enteric coronavirus (tcv) propagated in embryonating turkey eggs and were purified by density-gradient centrifugation. the specificity of antisera was confirmed by hemagglutination-inhibition and immunoelectron microscopy. absorption of anti-tcv hyperimmune sera with egg extracts o ... | 1989 | 2541641 |
| ultrastructure and protein a-gold immunolabelling of hrt-18 cells infected with turkey enteric coronavirus. | the minnesota strain of turkey enteric coronavirus (tcv) was propagated in hrt-18 cells, a cell line derived from human rectum adenocarcinoma. a productive non-cytopathic infection was established, without a previous adaptation, in these cells as shown by the specific hemagglutinating activity in cell culture supernatants. a post-embedding immunochemical technique, using specific antiserum directed against the original egg-adapted virus and colloidal-gold-labelled protein a as the electron-dense ... | 1989 | 2548321 |
| isolation and trypsin-enhanced propagation of turkey enteric (bluecomb) coronaviruses in a continuous human rectal adenocarcinoma cell line. | turkey enteric coronavirus (tcv) from intestinal contents of diarrheal poults was isolated and serially propagated in hrt-18 cells, an established cell line derived from a human rectal adenocarcinoma. in these cells, tcv induced cytopathic changes, including polykaryocytosis, which depended on trypsin in the medium and incubation at 41 c. viral antigens could be demonstrated in the cytoplasm by immunofluorescence, and extracellular virus was detected by an elisa and negative electron microscopy. ... | 1989 | 2551201 |
| hemorrhagic enteritis of turkeys: influence of maternal antibody and age at exposure. | the effect of maternal antibody (mab) to hemorrhagic enteritis (he) on the response of turkeys to infection with virulent and avirulent strains of he virus (hev) was examined. the influence of age at exposure and treatment with hev antibody on development of clinical he also was studied. mab protected poults from clinical he for up to 6 weeks of age. mab also interfered with vaccination against the disease for at least 5 weeks after hatching, as indicated by absence of hev antigen in spleens and ... | 1989 | 2559708 |
| turnip crinkle virus defective interfering rnas intensify viral symptoms and are generated de novo. | defective interfering (di) rnas have been isolated from a broad spectrum of animal viruses and have recently been identified in plant virus infections. because of their ubiquitous nature, dis are thought to play an important role in virus replication and yields. di rnas have now been found in association with a natural isolate of turnip crinkle virus (tcv-b) and are generated de novo after inoculation of turnip with virus derived from cloned transcripts. di rna g, naturally found in the tcv-b is ... | 1989 | 2594759 |
| identification and location of the structural glycoproteins of a tissue culture-adapted turkey enteric coronavirus. | the minnesota strain of turkey enteric coronavirus (tcv) was grown on a human rectal tumor (hrt-18) cell line in the presence of radiolabeled amino acids and glucosamine to analyse virion structural proteins. in addition to the 52,000 unglycosylated nucleocapsid protein, three major glycoprotein species were found to be associated with the viral envelope. a predominant glycosylated protein with a molecular weight of 22-24,000 represented the transmembrane matrix protein. larger glycoproteins wit ... | 1989 | 2673155 |
| turnip crinkle virus infection from rna synthesized in vitro. | genome-length cdna clones of turnip crinkle virus (tcv) were constructed with smai and xbai restriction sites engineered at the 5' and 3' termini, respectively. the genome-length cdnas were positioned downstream of modified lambda and t7 phage promoters such that in vitro transcription resulted in rnas with 5 extra nucleotides at the 3' end, and 1, 2, or 14 extra nucleotides at the 5' end depending on the construction. transcripts with 14 extraviral 5' nucleotides were not infectious, while tran ... | 1989 | 2718380 |
| the genome structure of turnip crinkle virus. | the nucleotide sequence of turnip crinkle virus (tcv) genomic rna has been determined from cdna clones representing most of the genome. segments were confirmed using dideoxynucleotide sequencing directly from viral rna, and the 3' terminal sequence was confirmed by chemical sequencing of end-labeled genomic rna. three open reading frames (orfs) have been identified by examination of the deduced amino acid sequences and by comparison with the orfs found in the genome of carnation mottle virus. or ... | 1989 | 2718381 |
| the complete nucleotide sequence of the maize chlorotic mottle virus genome. | the complete nucleotide sequence of the maize chlorotic mottle virus (mcmv) genome has been determined to be 4437 nucleotides. the viral genome has four long open reading frames (orfs) which could encode polypeptides of 31.6, 50, 8.9 and 25.1 kd. if the termination codons, for the polypeptides encoded by the 50 and 8.9 kd orfs are suppressed, readthrough products of 111 and 32.7 kd result. the 31.6 and 50 kd orfs overlap for nearly the entire length of the 31.6 kd orf. striking amino acid homolo ... | 1989 | 2726455 |
| the complete nucleotide sequence and genome organization of red clover necrotic mosaic virus rna-1. | the complete nucleotide sequence of red clover necrotic mosaic virus (rcnmv) rna-1 has been determined. rna-1 is 3889 nucleotides in length with a 5' terminal m7gpppa cap. the rna contains three large open reading frames (orfs): the 5' proximal orf, encoding a 27-kda polypeptide; the internal orf, coding for a 57-kda polypeptide; and the 3' terminal orf, encoding the 37-kda capsid protein. the sequence results confirm in vitro translation of 27-, 50-, and 37-kda products but do not account for t ... | 1989 | 2763465 |
| bean mild mosaic virus: genome and its translation products. | viral rna from purified preparations of bean mild mosaic virus (bmmv) was resolved into two rnas of mol. wt 1.5 x 10(6) daltons (r1) and 0.76 x 10(6) daltons (r2). complementary dna hybridizations, infectivity tests, and in-vitro translation studies established that r2 is a subgenomic rna derived from r1. in-vitro translation studies showed that the genomic rna (r1) coded for two major proteins of mol. wt. 40.5 kd and 25.7 kd. of these, the 40.5 kd protein was shown to be the capsid protein that ... | 1989 | 2763470 |
| intracellular synthesis and processing of the structural glycoproteins of turkey enteric coronavirus. | pulse labeling of cells with [35s]methionine or [3h]glucosamine at different times after infection, followed by sds-page and western immunoblotting analysis using rabbit anti-tcv hyperimmune serum, was used to resolve and identify tcv-induced intracellular proteins. the viral structural proteins (gp 200, gp 140/gp 66, gp 100/gp 120, p 52, and gp 24/p 20) were detected in radiolabeled cell extracts by 9 to 12 hours post-infection, as well as two possible non-structural proteins with apparent mol. ... | 1989 | 2774975 |
| a thin-layer multistrip agarose gel electrophoresis apparatus for ferguson plot analysis at the sub-microgram load level. | a method for the simultaneous horizontal agarose gel electrophoresis on thin-layer strips of different gel concentrations was developed for the purpose of generating ferguson plots at the sub-microgram load level. seven independent gel strips on a common gelbond support were formed by filling channels created by a comb-shaped spacer (polycarbonate) in a vertical multistrip cassette. electrophoresis on a horizontal peltier-cooled surface employed commercial apparatus (e-c apparatus corp.) with a ... | 1989 | 2809063 |
| viral agents associated with outbreaks of diarrhea in turkey flocks in quebec. | the relative importance of various enteric viruses associated with diarrhea of turkey poults was investigated by an evaluation of specimens received since 1982. specimens originated from one to eight week old turkey poults, with mild to severe diarrhea, from 114 flocks in 42 commercial operations located in southern quebec. the acute phase of enteritis occurred usually in poults between two and four weeks of age. clarified intestinal contents were examined by direct electron microscopy and enzym ... | 1988 | 2832044 |
| identification of the structural proteins of turkey enteric coronavirus. | coronaviruses in the intestinal contents of turkey poults from quebec flocks with outbreaks of enteritis were detected by electron microscopy. five isolates were serially propagated in embryonic turkey eggs by inoculation of clarified intestinal contents into the amniotic cavity. viral particles contained in the intestinal contents of infected embryos were purified by differential and isopycnic centrifugation in sucrose gradients. intact virions present in fractions of densities 1.18 to 1.20 g/m ... | 1988 | 2835946 |
| antitumor efficacy of two kinds of tumor vaccine modified with vaccinia virus. | we compared antitumor effectiveness of two types of tumor vaccine modified with vaccinia virus (vv). one type is uv-inactivated vv (uv-vv) -absorbed tumor cell vaccine (uv-vv tcv) produced by tumor cells that had been absorbed in vitro with uv-vv and subsequently x-irradiated with 10(4) rads. the other type is vaccinia oncolysate vaccine (vov) from tumor cells that had been infected in vitro with live vv and subsequently sonicated. c3h/hen mice were inoculated i.p. with uv-vv after whole body x- ... | 1988 | 2979853 |
| association of virulence of murine cytomegalovirus with macrophage susceptibility and with virion-bound non-neutralizing antibody. | a comparison was made of the virulence in vivo and the infectivity in vitro for macrophages of (i) tissue culture-passed mouse cytomegalovirus (mcmv), (ii) salivary gland virus taken 3 weeks after infection (sgv 3w), and (iii) salivary gland virus taken 1 week after infection (sgv 1w). salivary gland virus (3w) is known to be coated with non-neutralizing antibody, and is more virulent for newborn suckling mice and less infectious for macrophages than tissue culture-passed virus (tcv). properties ... | 1985 | 2984322 |
| respiratory disease (rhinotracheitis) of turkeys in brittany, france. iii. interaction of multiple infecting agents. | a candidate breeder flock of turkeys was studied during and after an outbreak of rhinotracheitis. laboratory studies revealed the presence of three pathogens during the acute phase of the disease. these agents were hemorrhagic enteritis virus (hev), paramyxovirus type 2 (pmv2), and chlamydia. twenty-five turkeys in the flock were individually identified, and blood samples from these birds were collected for serological studies each week for 21 weeks. the serological results revealed high titers ... | 1985 | 2985039 |
| enzyme immunoassay studies on the serological response of turkeys to hemorrhagic enteritis virus. | an enzyme-linked immunosorbent assay (elisa) was developed for the detection of antibodies in turkey serum to hemorrhagic enteritis virus. the elisa antigen was extracted from turkey spleens and partially purified with fluorocarbon. antibodies were demonstrated in serum samples of breeding and meat flocks that had been naturally exposed to infection. these samples were also examined in parallel by agar-gel precipitin (agp); most of the sera were agp-positive. elisa, however, was more sensitive i ... | 1985 | 2985040 |
| immunosuppressive effects of virulent strain of hemorrhagic enteritis virus in turkeys vaccinated against newcastle disease. | one week after infection with a virulent strain of hemorrhagic enteritis virus (hev), turkeys were vaccinated for newcastle disease. the effect of a virulent strain of hev on turkeys' immune response to newcastle disease vaccine and the mitogenic response of their whole blood peripheral lymphocytes were examined. the results revealed a statistically significant difference (p less than .01) in the newcastle disease hemagglutination inhibition (ndhi) antibody titers from turkeys infected with viru ... | 1985 | 2986088 |
| hemorrhagic enteritis of turkeys in california: serologic study of hemorrhagic enteritis virus antibody with an enzyme-linked immunosorbent assay. | the incidence of hemorrhagic enteritis (he) infection in california turkeys was studied by testing 2220 turkey blood samples from 173 flocks for he virus (hev) antibody by the enzyme-linked immunosorbent assay (elisa). maternal antibody was detected at 1 day of age in all flocks tested, and it vanished after 3 weeks. acquired hev antibody appeared at 8 to 10 weeks, and 100% of the meat and breeder turkey flocks were positive after 11 weeks of age. hev infection occurred earlier in the meat flock ... | 1985 | 2992436 |
| immunoelectrophoresis of avian viral proteins in a phosphate-buffered system. | avian influenza and hemorrhagic enteritis viral preparations were immunoelectrophoresed in a phosphate-buffered system. excellent separation and resolution of viral proteins were achieved. reasons are given why this method might be preferred over the conventional method employing a veronal (barbital)-buffered system. | 1985 | 3000333 |
| field outbreaks of colibacillosis of turkeys associated with hemorrhagic enteritis virus. | in a study of field material and a survey conducted by the authors, typical signs of colibacillosis of 6-to-12-week-old poults included sudden onset, listlessness, rales, and high mortality. signs persisted for about 2 weeks and were often followed by a low incidence of lameness caused by escherichia coli. gross lesions included enlarged and congested spleens and livers, and dilated discolored black or purple duodenal loops. microscopic lesions included splenic and hepatic congestion. in some bi ... | 1985 | 3000338 |
| coronaviruses associated with outbreaks of transmissible enteritis of turkeys in quebec: hemagglutination properties and cell cultivation. | coronaviruses were observed by electron microscopy in the intestinal contents of turkeys in quebec flocks where repeated outbreaks of enteritis occurred. three isolates could be serially propagated in turkey embryos inoculated by the amniotic route with clarified intestinal contents. purification and concentration of viral particles contained in intestinal contents of infected embryos were achieved by precipitation with polyethylene glycol and ultracentrifugation on sucrose density gradients. th ... | 1986 | 3015116 |
| quantitation of hemorrhagic enteritis virus antigen and antibody using enzyme-linked immunosorbent assays. | enzyme-linked immunosorbent assays (elisas) were developed to quantitate hemorrhagic enteritis virus (hev) antibodies in turkey sera and hev antigens in tissue extracts. these assays were more sensitive than the commonly used agar-gel precipitin tests in detecting antigen and antibody. the antibody-elisa was used to monitor the presence and decline of passive antibodies in turkey poults and the seroconversion of turkeys infected with hev. the antigen-elisa was carried out using a monoclonal anti ... | 1986 | 3028352 |
| further studies on in vitro and in vivo assays of hemorrhagic enteritis virus (hev). | isolation of hemorrhagic enteritis virus (hev) from spleens of infected turkeys in the mdtc-rp19 lymphoblastoid cell line was compared with detection of hev antigen in the same spleens using the agar gel precipitation (agp) test. a concordance of 80% was found between the two assays. virus isolation had a sensitivity of 84% and a specificity of 88% compared with the agp test. rp19 cells were also susceptible to infection with several other avian adenoviruses, but such infection was easily differ ... | 1987 | 3039962 |
| identification of regions affecting virulence, rna processing and infectivity in the virulent satellite of turnip crinkle virus. | turnip crinkle virus (tcv) supports a small family of satellite rnas (rnas c, d and f). rna c is a virulent satellite, producing severe symptoms in host plants, while rnas d and f are avirulent satellites. the virulent satellite (rna c) has two major domains--a 5'-domain similar to the avirulent satellites and a 3'-domain similar to the 3'-end of the tcv genome. to demonstrate that the 3'-domain of rna c determines virulence, a chimeric satellite was constructed composed mostly of the 5'-domain ... | 1988 | 3181135 |
| structure and assembly of turnip crinkle virus. iv. analysis of the coat protein gene and implications of the subunit primary structure. | the structure of the turnip crinkle virus (tcv) coat protein and coat protein gene has been examined by cdna cloning, nucleotide sequencing and high-resolution mrna mapping. we have cloned a 1450-nucleotide cdna fragment, representing the 3' end of the tcv genome, using genomic rna polyadenylated in vitro as the reverse transcriptional template. nucleic acid sequence analysis reveals the presence of a 1053 nucleotide open reading frame capable of encoding a protein of 38,131 mr, identified as th ... | 1987 | 3612806 |
| antibodies to marine caliciviruses in the pacific walrus (odobenus rosmarus divergens illiger). | sera from 155 pacific walruses (odobenus rosmarus divergens illiger), sampled in the chukchi sea during the summer of 1983, were tested for serum neutralizing (sn) antibodies to six marine calicivirus serotypes. serotypes tested included san miguel sea lion virus (smsv) types 1, 5, 8, and 10, previously isolated from northern fur seals (callorhinus ursinus linné) in the bering sea; walrus calicivirus (wcv), previously isolated from walrus feces collected off sea ice in the chukchi sea; and tilla ... | 1986 | 3712641 |
| structure and assembly of turnip crinkle virus. ii. mechanism of reassembly in vitro. | dissociation of turnip crinkle virus (tcv) at elevated ph and ionic strength produces free dimers of the coat protein and a ribonucleoprotein complex that contains the viral rna, six coat-protein subunits, and the minor protein species, p80 (a covalently linked coat-protein dimer). this "rp-complex" is stable for several days in high salt at ph 8.5. reassembly of tcv can be accomplished under physiological conditions, using isolated coat protein and either rp-complex or protein-free rna. if rp-c ... | 1986 | 3806677 |
| structure of turnip crinkle virus. iii. identification of a unique coat protein dimer. | the minor structural protein (p80), found in about one copy per virion in turnip crinkle virus (tcv), is shown by amino acid analysis and peptide mapping to be a covalent dimer of the major coat protein (p40). the covalent linkage occurs near the n termini of the crosslinked chains. these data suggest that tgv and related viruses contain 178 copies of p40 (89 non-covalent dimers) and one copy of p80 (covalent dimer of two additional p40 chains). the presence of p80 in the salt-stable rna-protein ... | 1986 | 3806680 |
| synthesis in vitro of infectious rna copies of the virulent satellite of turnip crinkle virus. | rna copies, synthesized in vitro, of the virulent satellite (rna c) of turnip crinkle virus (tcv) infect plants when coinoculated with helper virus rna. rna c is a small linear rna of about 355 bases which intensifies tcv symptoms in infected plants. full-length cdna copies of the satellite were inserted in an expression vector (for rna synthesis in vitro) in such a way that rna synthesized in vitro had the same 5'-end as the native satellite. plus-strand rna copies of the satellite in near-mono ... | 1987 | 3811230 |
| an enzyme-linked immunosorbent assay for detection of hemorrhagic enteritis virus and associated antibodies. | an enzyme-linked immunosorbent assay (elisa) that detects antibodies specific for type ii avian adenoviruses is described. freon-treated extracts from spleens of hemorrhagic enteritis (hev)-infected poults were a better source of antigen than the cell-culture-propagated virus. antigen-coated microtiter wells treated with bovine serum albumin reduced nonspecific adsorption of immunoglobulins. the elisa readily detected antibodies in hemorrhagic-enteritis- and marble-spleen-disease-infected field ... | 1984 | 6091606 |
| cell-mediated immunity against turkey coronaviral enteritis (bluecomb). | studies on cell-mediated immune response in turkeys infected with turkey coronavirus (tcv) were made. a whole blood culture technique was developed for quantitatively evaluating in vitro lymphocyte reactivity to mitogens concanavalin a, phytohemagglutinin-p, and tcv antigen. the degree of blastogenesis was quantitated by the measurement of the uptake of the [125i]deoxyuridine in the presence of fluorodeoxyuridine. the stimulation indices were consistently higher in the infected birds compared wi ... | 1980 | 6254402 |
| immunofluorescent studies on localization of secretory immunoglobulins in the intestines of turkeys recovered from turkey coronaviral enteritis. | the present study concerns the production of specific secretory antibodies in turkeys orally inoculated with turkey coronavirus (tcv). tissue localization of secretory antibodies in the intestines of recovered birds 4 and 5 months later was demonstrated by immunofluorescence technique. intestinal sections were stained by sandwich method, using concentrated tcv antigen and anti-tcv conjugate. it was suggested that local synthesis of antibody might be responsible for life-long immunity seen in the ... | 1980 | 6255832 |
| in vitro studies of hemorrhagic enteritis virus with immunofluorescent antibody technique. | dissociated spleen lymphocytes from hemorrhagic enteritis virus (hev)-free chickens, pheasants, and turkeys were infected with hev in suspension cultures. viral antigens were detected in cells of all three donor species by immunofluorescence. the age of chicken from which cells were obtained and the temperature of incubation influenced the development of viral antigens in cultured cells, which could be observed as early as 24 hr postinfection. this is the first time that hev has been shown to in ... | 1982 | 6284107 |
| immunofluorescence studies on the early pathogenesis of hemorrhagic enteritis virus infection in turkeys and chickens. | chickens and turkeys not previously exposed to hemorrhagic enteritis virus (hev) were inoculated orally with the virus. birds were necropsied each day from the first to the eighth day following inoculation, and specimens from various tissues were collected for examination. clinical illness was noted only in turkeys, although intestinal hemorrhages and swollen, necrotic spleens were seen in both species. the distribution and localization of viral antigens in various tissues and peripheral blood l ... | 1982 | 6284108 |
| field trials of an immunization procedure against hemorrhagic enteritis of turkeys. | the efficacy of oral vaccination for hemorrhagic enteritis of turkeys was assessed by comparing flocks raised on the same premises, under the same management, with and without vaccination. the immunizing virus, a strain of marble spleen disease virus of pheasants, was administered via the drinking water. vaccinated and unvaccinated turkeys differed significantly in feed conversion rates and spleen weights after challenge. | 1982 | 6293440 |
| evidence for bursal involvement in the pathogenesis of hemorrhagic enteritis of turkeys. | the pathogenesis of hemorrhagic enteritis in turkey poults infected with hemorrhagic enteritis virus (hev) at 3 days or at 2 or 5 weeks of age was compared with pathogenesis in poults that had been chemically bursectomized neonatally and exposed to cell-culture-propagated virus at 2 or 5 weeks of age. conventional poults exposed to hev at 2 or 5 weeks developed clinical disease, and mortality ranged from 38% to 100%. in addition to the splenic and intestinal lesions usually seen with hev infecti ... | 1982 | 6293443 |
| propagation of virulent and avirulent turkey hemorrhagic enteritis virus in cell culture. | virulent and apathogenic isolates of turkey hemorrhagic enteritis virus (hev) were successfully propagated in lymphoblastoid cell lines of turkey origin, whereas spleen and kidney cell cultures from hev-infected turkeys failed to replicate the virus. the lymphoblastoid cell lines used were mdtc-rp16 and mdtc-rp19, which were previously established from tumors induced by marek's disease virus in turkeys. virus replication followed co-cultivation of lymphoblastoid cells with spleen cells from hev- ... | 1982 | 6297447 |
| hemorrhagic enteritis in turkeys: purification and quantification of the virus. | two methods for purifying the virus of hemorrhagic enteritis from infected turkey spleens are described. one procedure utilized precipitation with polyethylene glycol, and the other consisted of trichlorotrifluoroethane extraction. both procedures included sucrose-cesium chloride gradient centrifugation in the final purification step. the buoyant density of the viral fraction was 1.34 g/cm3, typical for adenoviral particles, and the size and morphologic characteristics of the virions observed by ... | 1983 | 6303291 |
| haemorrhagic enteritis of turkeys: comparison of two serological assays for detecting antibodies in one-day-old poults, sick and convalescent turkeys. | | 1983 | 6316625 |
| role of splenectomy in prevention of hemorrhagic enteritis and death from hemorrhagic enteritis virus in turkeys. | hemorrhagic diarrhea, gross hemorrhagic enteritis, and death caused by intravenous virus injection of hemorrhagic enteritis virus (hev) were prevented in otherwise susceptible turkey poults by surgical splenectomy. the splenectomized poults produced anti-hev antibodies, which indicated that splenectomy did not completely prevent replication of the virus. these results indicate that the spleen is necessary for the development of the intestinal lesions of this disease. the role of a toxic factor i ... | 1983 | 6316896 |
| requirement of a 3'-terminal stem-loop in in vitro transcription by an rna-dependent rna polymerase. | partially purified rna-dependent rna polymerase (rdrp) isolated from plants infected with turnip crinkle virus (tcv) is capable of template-dependent synthesis of tcv-associated rnas. to determine the cis-sequences required for the synthesis of tcv satellite (sat-) rna c (-) strands in vitro, templates containing interior deletions were subjected to transcription using rdrp-active fractions. results indicated that the promoter for (-)-strand synthesis was contained within the 3'-terminal 29 base ... | 1995 | 7473759 |
| hemorrhagic enteritis virus induced changes in the lymphocyte subpopulations in turkeys and the effect of experimental immunodeficiency on viral pathogenesis. | we examined the changes in the lymphocyte subpopulations in the spleen and peripheral blood of turkeys and the effects of experimental immunodeficiency in the b and t cell compartments on the pathogenesis of hemorrhagic enteritis (he) in turkeys. inoculation of turkeys with hemorrhagic enteritis virus (hev) induced a drop in the relative proportions of igm bearing cells on day 2, 3, and 9 post-infection and an elevation in the relative proportions of cd4+ cells on day 4 and 6 post-infection. ele ... | 1995 | 7604531 |
| immunodetection, expression strategy and complementation of turnip crinkle virus p28 and p88 replication components. | the plus-sense rna genome of turnip crinkle virus (tcv) encodes at its 5' end a 28-kda protein of unspecified function. readthrough suppression of the p28 stop codon allows for the production of an 88-kda product which is required for genome replication. immunological analysis of the expression of p28 and p88 demonstrated that: (i) the genome directs the synthesis of polypeptides of approximately 28 and 88 kda, (ii) the 88-kda protein is immunologically related to p28, consistent with p88 being ... | 1995 | 7645256 |
| effect of infection with hemorrhagic enteritis virus on susceptibility of turkeys to escherichia coli. | the present study was designed to investigate hemorrhagic enteritis virus (hev) as a predisposing factor influencing the susceptibility of young turkeys to escherichia coli infections. in addition, the pathologic changes caused by administration of e. coli by various routes were compared. following oral infection with hev, groups of turkeys were inoculated with various doses of pathogenic e. coli by intravenous (iv), intra-air sac (ia), or intratracheal (it) routes. a synergistic effect was obse ... | 1994 | 7702502 |
| preliminary studies of primary ostrich fibroblasts for the isolation of ratite viruses. | an ostrich egg at 21 days of development was used to propagate primary embryo cell cultures. primary cultures of skeletal muscle cells (for fibroblasts) were prepared by routine typsinization techniques. the ostrich embryo fibroblasts were tested for their ability to propagate stock avian viruses of infectious bronchitis virus, paramyxiovirus-1 (pmv-1), pmv-2, pmv-3, infectious bursal disease virus, quail bronchitis virus, avian reovirus, turkey coronavirus, and two ostrich-originating specimens ... | 1994 | 7702522 |
| quantitative analysis of the binding of turnip crinkle virus coat protein to rna fails to demonstrate binding specificity but reveals a highly cooperative assembly interaction. | an element(s) within a 386-nucleotide segment (tcv-386 rna) of the turnip crinkle virus (tcv) genome was previously implicated in virus assembly nucleation. to localize the proposed high-affinity binding determinants, we analyzed the ability of the coat protein to bind the full-length and truncated derivatives of the tcv-386 rna using gel retardation and nitrocellulose filter retention assays. quantitation of the binding data indicated that the coat protein did not preferentially recognize a par ... | 1995 | 7793083 |
| response of specific-pathogen-free turkeys to vaccines derived from marble spleen disease virus and hemorrhagic enteritis virus. | tissue-culture-propagated marble spleen disease virus (msdv-tc) and two preparations of spleen homogenate (msdv-sh and msdv-sh-tc) were compared as anti-hemorrhagic enteritis virus (hev) vaccines in specific-pathogen-free turkeys. both types of vaccines spread horizontally among turkeys, induced anti-hev antibodies, and protected turkeys against challenge with virulent hev. antibody development and horizontal spread of virus occurred earlier in turkeys given msdv-sh or msdv-sh-tc than in those g ... | 1994 | 7832705 |
| an angiotensin ii receptor antagonist reduces myocardial damage in an animal model of myocarditis. | recently, an angiotensin-converting enzyme inhibitor was shown to have a beneficial effect on virus-induced myocardial injury. we investigated the effect of a new angiotensin ii type 1 receptor antagonist, (+-)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-([2'-(1h-tetrazol-5-yl)biphenyl-4-yl]methyl)-1h-benz imi dazole-7- carboxylate (tcv-116), in an animal model of viral myocarditis induced by encephalomyocarditis virus. | 1994 | 7923693 |
| rna-dependent rna polymerase from plants infected with turnip crinkle virus can transcribe (+)- and (-)-strands of virus-associated rnas. | rna-dependent rna polymerase (rdrp) was solubilized from membranes of turnip infected with turnip crinkle virus (tcv), a single-stranded, monopartite rna virus. the rdrp activity could be separated into three peaks by sephacryl s500hr chromatography. rdrp from peak i, which contained substantial amounts of endogenous tcv genomic rna, and peak ii were template-specific, synthesizing full-length complementary strands of exogenous tcv subviral rnas but not control rna templates. peak iii rdrp was n ... | 1994 | 8090725 |
| recombination between plus and minus strands of turnip crinkle virus. | turnip crinkle virus (tcv), a small monopartite rna virus, is associated with several subviral rnas, some of which are the products of recombination between the genomic rna and an unrelated satellite rna (sat-rna d). as part of a study on the nonrandom sequences found at the junctions of nearly all tcv recombinant molecules, we have characterized a novel recombinant (d/tcv950) that was formed from sat-rna d and both the plus and minus strands of the genomic rna. d/tcv950 (517 nt) is composed of ... | 1994 | 8184554 |
| asp-->asn substitutions in the putative calcium-binding site of the turnip crinkle virus coat protein affect virus movement in plants. | many plant virus coat proteins have binding sites for divalent cations, particularly calcium. it has been speculated that the purpose of such sites is to ensure that plant viruses release their rna only in the host cytoplasm which has a low calcium concentration. by comparison to tomato bushy stunt virus, two of the amino acids that probably interact directly with calcium ions in turnip crinkle virus (tcv) capsids, asp155 and asp157, were substituted with asn residues by oligonucleotide-directed ... | 1993 | 8249300 |
| characterization of monoclonal antibodies to bovine enteric coronavirus and antigenic variability among quebec isolates. | twenty monoclonal antibodies (mabs) were prepared against the mebus strain of bovine enteric coronavirus, 14 of them reacting with the peplomeric s (gp 100) glycoprotein. competition binding assays allowed the definition of at least 4 distinct antigenic domains for the s glycoprotein, designated as a, b, c, and d; epitopes associated to neutralizing activity being located in sites a, b, and c. one mab directed to the hemagglutinin he (gp 140/gp 65) glycoprotein inhibited the hemagglutinating act ... | 1993 | 8347084 |
| evaluation of cell culture propagated and in vivo propagated hemorrhagic enteritis vaccines in turkeys. | the immune response of turkeys to a liquid, was compared with a previously frozen, cell culture propagated hemorrhagic enteritis (he) vaccine. the liquid cell culture propagated he vaccine was able to induce 100% seroconversion in turkeys 4 weeks after being vaccinated at 3.5 weeks of age; however, the previously frozen cell culture propagated he vaccine induced 80% seroconversion 4 weeks post vaccination (p < 0.05). the average seroconversion in turkey flocks administered the liquid cell cultur ... | 1993 | 8381570 |
| a monoclonal antibody-based immunoperoxidase method for rapid detection of haemorrhagic enteritis virus of turkeys. | an indirect immunoperoxidase (ip) technique involving avidin-biotin peroxidase complex, using a monoclonal antibody was developed for the detection of haemorrhagic enteritis (he) virus antigen in frozen and formalin-fixed paraffin-embedded tissue sections. this ip procedure was compared with an indirect immunofluorescence antibody technique (ifat) and an agar gel precipitation test (agpt). spleens from turkeys experimentally infected with he virus were collected and examined for the presence of ... | 1993 | 8397435 |
| in vivo restoration of biologically active 3' ends of virus-associated rnas by nonhomologous rna recombination and replacement of a terminal motif. | sequences at the 3' ends of plus-strand rna viruses and their associated subviral rnas are important cis elements for the synthesis of minus strands in vivo and in vitro. all rnas associated with turnip crinkle virus (tcv), including the genomic rna (4,054 bases) and satellite rnas (sat-rnas) such as sat-rna d (194 bases), terminate with the motif ccugccc. while investigating the ability of in vivo-generated recombinants between sat-rna d and tcv to be amplified in plants, we discovered that sat ... | 1996 | 8523561 |
| open reading frames of turnip crinkle virus involved in satellite symptom expression and incompatibility with arabidopsis thaliana ecotype dijon. | carmoviruses are single-stranded, single component rna viruses that include turnip crinkle virus (tcv) and the recently discovered cardamine chlorotic fleck virus (ccfv). full-length, biologically active cdnas were constructed for the tcv-m isolate and the blue lake isolate of ccfv. using chimeric viruses constructed between isolates of tcv that produce mild or severe symptoms when coinoculated with a virulent satellite rna, a glu residue at position 1,144 in the polymerase open reading frame wa ... | 1995 | 8664506 |
| immunomodulating agents for the management of heart failure with myocarditis and cardiomyopathy--lessons from animal experiments. | we have developed murine models of viral myocarditis induced by the encephalomyocarditis (emc) virus in which there is a high incidence of severe myocarditis, congestive heart failure and dilated cardiomyopathy. from these models, we have learned of their natural history and pathogenesis and assessed new diagnostic methods and therapeutic and preventive interventions. our recent studies showed that increased circulating cytokines have been detected in patients with acute myocarditis and cardiomy ... | 1995 | 8682082 |
| changes in locations of crossover sites over time in de novo generated rna recombinants. | recombinant rnas generated in plants 3 weeks postinoculation with turnip crinkle virus (tcv) genomic rna and an associated satellite rna, sat-rna d, have a majority of tcv crossover sites in a 24-nucleotide repeat (motif iiia/iiib) that forms part of a stable hairpin (carpenter et al., 1995, j. mol.biol. 245, 608-622). to determine if parameters other than nucleotide sequence in the crossover region affect junction site selection, recombinants were assayed at various times postinoculation of pla ... | 1996 | 8806550 |
| in vivo repair of 3'-end deletions in a tcv satellite rna may involve two abortive synthesis and priming events. | rna viruses that do not have the stabilizing features of poly(a) tails or amino acids covalently linked to their 3' ends must develop other means for protecting or repairing their genomes from damage caused by cellular rnases. we previously found that deletions in the single-stranded tails of a satellite rna (sat-rna d) associated with turnip crinkle virus are repaired in vivo (c. d. carpenter and a. e. simon, 1996, j. virol. 70, 478-486). we now extend this analysis to show that sat-rna d trans ... | 1996 | 8955033 |
| encapsidation of turnip crinkle virus is defined by a specific packaging signal and rna size. | a protoplast infection assay has been used to reliably examine the viral rna encapsidation of turnip crinkle virus (tcv). analysis of the encapsidation of various mutant viral rnas revealed that a 186-nucleotide (nt) region at the 3' end of the coat protein (cp) gene, with a bulged hairpin loop of 28 nt as its most essential element, was indispensable for tcv rna encapsidation. when rna fragments containing the 186-nt region were used to replace the cp gene of a different virus, tomato bushy stu ... | 1997 | 8995668 |
| identification of an arabidopsis locus required for resistance to turnip crinkle virus. | inoculation of turnip crinkle virus (tcv) into a (tcv)-resistant line of arabidopsis thaliana, di-17, results in the development of a hypersensitive response (hr) on the inoculated leaves. in contrast, an hr does not occur when leaves of the tcv-susceptible di-3 line or the susceptible ecotypes columbia (col-0), or landsberg erecta (ler) are inoculated. genetic analysis of progeny from crosses between di-17 and either di-3, col-0 or ler demonstrates that the development of an hr is regulated by ... | 1997 | 9076995 |
| analysis of the two subgenomic rna promoters for turnip crinkle virus in vivo and in vitro. | infection of plants or protoplasts with turnip crinkle virus (tcv), a monopartite rna virus, results in the synthesis of the genomic rna and two subgenomic (sg) rnas. the transcription start site for the 1.45-kb sgrna was previously mapped to position 2606 (j. c. carrington, t. j. morris, p. g. stockley, and s. c. harrison, (1987). j. mol. biol. 194, 265-276) corresponding to position 2607 in the tcvms isolate and the start site for the 1.7-kb sgrna has now been mapped to position 2333 in tcvms. ... | 1997 | 9185601 |
| antigenic characterization of a turkey coronavirus identified in poult enteritis- and mortality syndrome-affected turkeys. | a turkey coronavirus (tcv [nc95]) was characterized by antigenic comparison with other avian and mammalian coronaviruses using immunofluorescence (fa) and immunoperoxidase (ip) procedures. based on fa and ip procedures, tcv (nc95) was determined to be antigenically indistinguishable from turkey enteric (bluecomb) coronavirus (tecv). in addition, tcv (nc95) and tecv were found to be closely related to infectious bronchitis virus (ibv); a one-way antigenic relationship was demonstrated. polyclonal ... | 1997 | 9356703 |
| spiking mortality of turkey poults: 1. experimental reproduction in isolation facilities. | spiking mortality of turkeys (smt) is an infectious disease of 5-to-25-day-old turkey poults characterized by acute enteritis and bursal and thymic atrophy. brooding 1-day-old poults on litter taken from naturally occurring cases successfully reproduced smt 5 days postexposure. oral exposure to an organ homogenate made of tissue samples from naturally occurring cases successfully reproduced smt 5 days postinoculation. coronaviruses were present in intestinal and bursal contents taken from poults ... | 1997 | 9356706 |
| analysis in vivo of turnip crinkle virus satellite rna c variants with mutations in the 3'-terminal minus-strand promoter. | turnip crinkle virus and its associated rna, sat-rna c, share similar, but not identical hairpins near their 3' ends and terminate with ccugccc-oh, which forms a single-stranded tail. with an in vitro transcription system containing partially purified tcv rdrp, the 3'-terminal 29 bases making up the hairpin and single-stranded tail were previously demonstrated to be required for transcription, and alterations in the stem, but not the loop, could affect template activity (c. song and a. e. simon, ... | 1997 | 9400619 |
| the coat protein of turnip crinkle virus is involved in subviral rna-mediated symptom modulation and accumulation. | some satellite (sat-) and defective interfering (di) rnas associated with plant viruses intensify or ameliorate the symptoms of the virus. we recently demonstrated that the tcv coat protein (cp) is involved in symptom modulation by sat-rna c. two additional subviral rnas have now been tested for effect of the cp on symptom modulation. di rna g, which normally intensifies the symptoms of tcv, is able to attenuate symptoms if the tcv cp is replaced with the cp of cardamine chlorotic fleck virus. d ... | 1997 | 9400620 |
| satellite rna-mediated resistance to turnip crinkle virus in arabidopsis involves a reduction in virus movement. | satellite rnas (sat-rnas) are parasites of viruses that can mediate resistance to the helper virus. we previously showed that a sat-rna (sat-rna c) of turnip crinkle virus (tcv), which normally intensifies symptoms of tcv, is able to attenuate symptoms when tcv contains the coat protein (cp) of cardamine chlorotic fleck virus (tcv-cpccfv). we have now determined that sat-rna c also attenuates symptoms of tcv containing an alteration in the initiating aug of the cp open reading frame (tcv-cpm). t ... | 1997 | 9401127 |
| rna promoters located on (-)-strands of a subviral rna associated with turnip crinkle virus. | satellite (sat-) rna c, one of the nonessential subviral rnas of turnip crinkle virus (tcv), is dependent on the tcv-encoded rna-dependent rna polymerase (rdrp) for its replication. earlier work showed that a stem-loop structure at the 3' end of (+)-strand sat-rna c is required for synthesis of (-)-strands in vitro using a partially purified, template-specific tcv rdrp (song c, simon ae, 1995, j mol biol 254:6-14). cis-sequences on (-)-strands of sat-rna c that can serve as separate promoters in ... | 1997 | 9404891 |
| spiking mortality of turkey poults: 2. effect of six different in vitro disinfection techniques on organ homogenates capable of reproducing smt. | spiking mortality of turkeys (smt) is an infectious disease of 5-to-25-day-old turkey poults characterized by acute enteritis and bursal and thymic atrophy. it is reproducible by exposure to organ homogenates or contaminated litter. we studied methods potentially useful for decontamination of turkey houses contaminated with smt. organ homogenates capable of producing smt and containing turkey intestinal coronavirus were exposed in vitro for 5 hr to either 5.0% nacl, ph 2.0, ph 12, 1.0% formaldeh ... | 1997 | 9454925 |
| molecular cloning and complete nucleotide sequence of galinsoga mosaic virus genomic rna. | the complete genomic sequence of galinsoga mosaic virus (gamv) was determined. the genome consists of 3,803 nucleotides and has five open reading frames (orfs). the 5' orf (orf 1) encodes a protein with predicted molecular mass of 23 kda and readthrough of its amber stop codon probably yields a 82 kda protein (orf 2). orfs 3 and 4 encode two polypeptides with molecular masses of 8 and 7 kda, respectively. orf 5 encodes the 36 kda capsid protein. amino acid sequence comparisons revealed that the ... | 1998 | 9505975 |
| analysis of sequences and predicted structures required for viral satellite rna accumulation by in vivo genetic selection. | in vivo genetic selection was used to study the sequences and structures required for accumulation of subviral sat-rna c associated with turnip crinkle virus (tcv). this technique is advantageous over site-specific mutagenesis by allowing side-by-side selection from numerous sequence possibilities as well as sequence evolution. a 22 base hairpin and 6 base single-stranded tail located at the 3'-terminus of sat-rna c were previously identified as the promoter for minus strand synthesis. approxima ... | 1998 | 9580696 |
| cell-to-cell movement of turnip crinkle virus is controlled by two small open reading frames that function in trans. | previous studies on turnip crinkle virus (tcv) have suggested that the two small, centrally located orfs, conserved in all carmoviruses, are both required for cell-to-cell movement (hacker et al., 1992). we now demonstrate that the cell-to-cell movement of tcv is mediated by in trans complementation of the two proteins. first, both of the putative movement proteins (mps p8 and p9) were shown to be translated in vitro from transcripts representing the 1.7-kb subgenomic rna. western blot analysis, ... | 1998 | 9601509 |