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1.
Epidemiol Infect ; 147: e90, 2019 01.
Article in English | MEDLINE | ID: mdl-30869004

ABSTRACT

Enteric pathogens have been related to child undernutrition. Whereas there are lots of data on enteric bacterial microbiota and infections, much less is known about the incidence of prevalence of intestinal colonisation with viruses or important parasitic species. This study assessed the presence of selected viruses and parasites in stools of 469, 354, 468 Malawian children at 6, 12 and 18 months. We also assessed environmental predictors of the presence of viruses and parasites among 6-month infants. Microbial presence was documented using real-time polymerase chain reaction (PCR). Enteroviruses were identified in 68%, 80% and 81% of the stool samples at 6, 12 and 18 months children, rhinovirus in 28%, 18% and 31%, norovirus in 24%, 22% and 16%, parechovirus in 23%, 17% and 17%, rotavirus in 3%, 1% and 0.6%, Giardia lamblia in 9.6%, 23.5% and 26%, and Cryptosporidium (spp.) in 6%, 8% and 2% of the 6, 12 and 18 months stool samples. Dry season (May-October) was associated with a low infection rate of enterovirus, norovirus and Cryptosporidium (spp.). Higher father's education level, less number of person in the household and higher sanitation were associated with a low infection rate of enterovirus, norovirus and rotavirus, respectively. The results suggest that the prevalence of asymptomatic viral and parasitic infections is high among Malawian children and that the family's living conditions and seasonality influence the rate of infections.


Subject(s)
Parasitic Diseases/epidemiology , Rural Population/statistics & numerical data , Virus Diseases/epidemiology , Cross-Sectional Studies , Female , Humans , Infant , Malawi/epidemiology , Male , Parasitic Diseases/parasitology , Prevalence , Virus Diseases/virology
2.
Tech Coloproctol ; 22(3): 209-214, 2018 03.
Article in English | MEDLINE | ID: mdl-29546469

ABSTRACT

BACKGROUND: The aim of the present study was to evaluate the subjective outcome of primary repair of obstetric anal sphincter injury (OASIS) at 6 months, the factors associated with the symptoms of anal incontinence (AI), and the role of a simple survey consisting in one question with three answer choices, combined with the Wexner incontinence score for the assessment of this patient population. METHODS: A retrospective cohort study was conducted on patients with third- or fourth-degree OASIS operated on between January 2007 and December 2013 inclusive at Tampere University Hospital, Finland. At 6 months, the patients were asked to report their Wexner's score as well as the three-choice assessment regarding AI symptoms. Based on this assessment, the patients were divided into three groups: those, asymptomatic, those with mild symptoms who did not want further treatment and those with severe symptoms who were willing to undergo further evaluation and treatment. RESULTS: There were 325 patients (median age 30 years). A total of 310 patients answered the questionnaire. Of which, one hundred and ninety-eight (63.9%) patients were asymptomatic, 85 (27.4%) had mild AI, and 27 (8.7%) experienced severe symptoms. There was no statistical difference in the results between the two techniques used (overlapping vs. end-to-end), or the stage of specialization of the operating physician. Persistent symptoms were associated with instrumental vaginal delivery (OR 2.12, 95% CI 1.32-3.41), severity of the injury (OR 1.64, 95% CI 1.20-2.25), and increased maternal age (OR 1.07, 95% CI 1.02-1.13). The correlation between the three-choice symptom evaluation and the Wexner score was good (Spearman's rho 0.82). CONCLUSIONS: After 6 months, severe symptoms after OASIS repair were present in 9% of women and were more frequent in older women, women with high-degree tears and after instrumental vaginal delivery. A three-choice assessment of AI symptoms correlated well with the Wexner score and might be useful to triage patients who need further evaluation.


Subject(s)
Anal Canal/injuries , Anal Canal/surgery , Delivery, Obstetric/adverse effects , Fecal Incontinence/etiology , Severity of Illness Index , Surveys and Questionnaires , Adult , Delivery, Obstetric/methods , Extraction, Obstetrical/adverse effects , Female , Humans , Manometry , Maternal Age , Pregnancy , Retrospective Studies , Symptom Assessment , Trauma Severity Indices
3.
Tech Coloproctol ; 20(1): 25-9, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26519287

ABSTRACT

BACKGROUND: Antegrade colonic enemas are used in patients with colorectal dysfunction resistant to conservative therapy. A number of different operative techniques are applied, but their effectiveness is by and large unknown. We therefore evaluated the long-term usefulness of the left-sided percutaneous endoscopic gastrostomy (PEG) tube method in adult patients. METHODS: Twenty-one patients with colorectal dysfunction underwent insertion of a PEG tube colostomy by laparotomy between 1997 and 2006. In 2014, we evaluated how many of the patients had the tube still in place, how the patients coped with the tube, and what the reasons for the removal were. RESULTS: The main indications were severe constipation or fecal incontinence mainly related to neurological diseases. In 2014, 5 out of 21 patients had the tube still in use (median follow-up 14 years, range 11-17 years) and 4 out of 5 deceased patients had had the tube in use until their death, unrelated to this treatment (median follow-up 7 years, range 0-8 years). Four out of the 5 living patients considered the benefit of the tube to be good or excellent. Tubes were removed in 11 (52%) patients for various reasons, local skin irritation being the most common. CONCLUSIONS: A left-sided PEG tube colostomy was removed in over half of the patients, but despite that, it still seems to be a viable long-term option in the treatment of individual patients with colorectal dysfunction, when conservative methods are ineffective.


Subject(s)
Colonic Diseases, Functional/therapy , Endoscopy, Gastrointestinal/methods , Enema/methods , Gastrostomy/methods , Adult , Aged , Colon, Sigmoid/surgery , Constipation/therapy , Fecal Incontinence/therapy , Female , Follow-Up Studies , Gastrostomy/instrumentation , Humans , Male , Middle Aged , Prospective Studies , Time Factors , Treatment Outcome
4.
Eur Psychiatry ; 28(8): 492-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23928267

ABSTRACT

The COMT Val158Met polymorphism has been associated with anxiety and affective disorders, but its effect on anxiety-related personality traits varies between studies. Our purpose was to investigate the effect of COMT Val158Met on personality traits from adolescence to young adulthood in a population representative Caucasian birth cohort. Also its association with educational attainment and anxiety and mood disorders by the age 25 were examined. This analysis is based on the older cohort of the Estonian Children Personality Behavior and Health Study (original number of subjects 593). The personality traits were assessed when the participants were 15, 18 and 25 years old. COMT Val158Met had an effect on Neuroticism in females by age 25 (p=0.001, Bonferroni-corrected for five traits), whereas female Val homozygotes scored the highest. In addition, the Conscientiousness scores of subjects with Val/Val genotype were decreasing in time, being the lowest by the age 25 (p=0.006, Bonferroni-corrected for five traits). By the age 25, males with the Val/Met genotype had mainly secondary or vocational education, whereas female heterozygotes mostly had obtained or were obtaining university education. COMT Val158Met was not associated with anxiety or mood disorders in either gender. These results suggest that genes affecting dopamine system are involved in the development of personality traits and contribute to educational attainment.


Subject(s)
Achievement , Catechol O-Methyltransferase/genetics , Personality/genetics , Polymorphism, Single Nucleotide , Adolescent , Adult , Anxiety Disorders/genetics , Educational Status , Female , Gene Frequency , Genotype , Humans , Longitudinal Studies , Male , Mood Disorders/genetics , Sex Factors
5.
Colorectal Dis ; 12(7): 687-91, 2010 Jul.
Article in English | MEDLINE | ID: mdl-19486087

ABSTRACT

OBJECTIVE: The aim of this study was to estimate the prevalence of and factors associated with faecal incontinence in a Finnish population. METHOD: A population-based age-stratified random sample of 8000 people aged 30-81 years from a large city was obtained from the national population registry. A postal questionnaire was sent to all subjects. Questions regarding faecal incontinence were adopted from a previously developed validated questionnaire. RESULTS: Response rate was 39.8%. Overall, the prevalence of faecal incontinence occurring in any frequency within the last year was 10.6% (CI: 9.5-11.6%). Women suffered significantly more often than men (11.9% vs. 8.7%). The prevalence of faecal incontinence occurring at least twice a month was 5.2% (CI: 4.5-6%). Of these subjects, 62.3% used a pad at least twice a month to protect their underwear (91 women, 10 men), 23.6% used it daily. There was a strong correlation between faecal incontinence and urinary incontinence. Of the 162 subjects reporting faecal incontinence at least twice a month, only 27.2% had discussed the problem with their physician. In 12.4%, their physician had raised the question of faecal incontinence. Only 10% had received treatment for it, but 66% (107/162) felt they needed treatment. CONCLUSION: Faecal incontinence is a common problem. Only a minority had reported this symptom to their physician and surprisingly few had received treatment for it. General awareness of faecal incontinence and treatment options should be improved among primary care physicians and general population.


Subject(s)
Fecal Incontinence/epidemiology , Population Surveillance , Adult , Age Distribution , Aged , Aged, 80 and over , Female , Finland/epidemiology , Follow-Up Studies , Humans , Male , Middle Aged , Prevalence , Risk Factors , Sex Distribution
6.
Mol Plant Microbe Interact ; 20(12): 1489-94, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17990956

ABSTRACT

Full-length cDNAs of the wild-type (wt) Tobacco mosaic virus (TMV) and of the coat protein gene-deleted (DeltaCP) derivative of wt-TMV, under control of the 35S promoter and downstream ribozyme sequence to produce accurate viral transcripts, were transformed to tobacco plants to analyze plant-virus interactions through different stages of plant development. Surprisingly, young wt-TMV transgenics accumulated only very low levels of viral RNA, remained free of symptoms, and were moderately resistant against exogenous inoculations. This early resistance caused significant stress to the plants, as indicated by reduced growth. Approximately 7 to 8 weeks after germination, the resistance was broken and plants developed typical wt-TMV symptoms, with high accumulation of the viral RNAs and proteins. The DeltaCP-TMV plants likewise were initially resistant to the endogenous inoculum and were stunted, although to a lesser extent than the wt-TMV plants. The resistance was broken at the same time as in the wt-TMV plants, but the mutant replicated to much lower levels and produced much milder symptoms than the wt virus. TMV-specific small interfering RNAs as well as increased transgene methylation were detected in the plants only after the resistance break, indicating that the resistance in the young plants was not due to RNA silencing.


Subject(s)
Genome, Viral , Nicotiana/virology , Plant Diseases/virology , Plants, Genetically Modified/virology , Tobacco Mosaic Virus/genetics , DNA Methylation , Immunity, Innate , Plants, Genetically Modified/metabolism , RNA, Viral/metabolism , Nicotiana/genetics , Nicotiana/growth & development
7.
Arch Virol ; 152(9): 1767-74, 2007.
Article in English | MEDLINE | ID: mdl-17585366

ABSTRACT

The genus Nepovirus (family Comoviridae) was known both for a good level of homogeneity and for the presence of atypical members. In particular, the atypical members of the genus differed by the number of capsid protein (CP) subunits. While typical nepoviruses have a single CP subunit with three structural domains, atypical nepoviruses have either three small CP subunits, probably corresponding to the three individual domains, or a large and a small subunit, probably containing two and one structural domains, respectively. These differences are corroborated by hierarchical clustering based on sequences derived from both genomic RNAs. Therefore, these atypical viruses are now classified in two distinct genera, Cheravirus (three CP subunits; type species Cherry rasp leaf virus) and Sadwavirus (two CP subunits; type species Satsuma dwarf virus).


Subject(s)
Genome, Viral/genetics , Plant Viruses/genetics , RNA Viruses/classification , Secoviridae/classification , Nepovirus/classification , Phylogeny , Plant Viruses/isolation & purification , RNA Viruses/genetics , Secoviridae/chemistry , Secoviridae/genetics
8.
Arch Virol ; 149(9): 1867-75, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15593427

ABSTRACT

Blackcurrant reversion virus (BRV) belongs in the subgroup c of nepoviruses. The 3' NTRs of RNAs 1 and 2 of BRV are 1360 and 1363 nucleotides long, respectively, and highly similar (94.8%). In this study we have compared the sequences of the 3' NTRs of ten BRV isolates, originating from different geographic regions or hosts. All deduced sequences were 94.1-98.8% identical with each other, and with the previously deduced 3' NTR sequences of RNAsl and 2 of the type isolate. The proceeding 480 nucleotides of the CP coding region were 86.9-97.9% identical between the same isolates.


Subject(s)
3' Untranslated Regions , Conserved Sequence , Nepovirus/genetics , Base Sequence , Capsid Proteins/genetics , Molecular Sequence Data , Nepovirus/isolation & purification , Phylogeny , Sequence Alignment , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
9.
J Gen Virol ; 83(Pt 3): 651-662, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11842260

ABSTRACT

The movement function of poa semilatent hordeivirus (PSLV) is mediated by the triple gene block (TGB) proteins, of which two, TGBp2 and TGBp3, are membrane proteins. TGBp3 is localized to peripheral bodies in the vicinity of the plasma membrane and is able to re-direct TGBp2 from the endoplasmic reticulum (ER) to the peripheral bodies. For imaging of TGBp3-mediated protein targeting, PSLV TGBp3 tagged with a red fluorescent protein (DsRed) was used. Coexpression of DsRed-TGBp3 with GFP targeted to the ER lumen (ER-GFP) demonstrated that ER-GFP was contained in typical ER structures and peripheral bodies formed by TGBp3 protein, suggesting an ER origin for these bodies. In transient coexpression with viral membrane proteins tagged with GFP, DsRed-TGBp3 directed to the peripheral bodies the homologous TGBp2 protein and two unrelated membrane proteins, the 6 kDa movement protein of beet yellows closterovirus and the putative movement protein encoded by the genome component 4 of faba bean necrotic yellows nanovirus. However, coexpression of TGBp3 with GFP derivatives targeted to the ER membranes by artificial hydrophobic tail sequences suggested that targeting to the ER membranes per se was not sufficient for TGBp3-directed protein trafficking to peripheral bodies. TGBp3-induced targeting of TGBp2 also occurred in mammalian cells, indicating the universal nature of the protein trafficking signals and the cotargeting mechanism.


Subject(s)
Membrane Proteins/metabolism , Nanovirus , Nicotiana/cytology , Nicotiana/metabolism , Viral Proteins/metabolism , Animals , Caveolin 1 , Caveolins/metabolism , Cell Line , Cell Membrane/metabolism , Closterovirus , Color , Cricetinae , Endoplasmic Reticulum/metabolism , Gene Expression , Green Fluorescent Proteins , Humans , Luminescent Proteins/metabolism , Membrane Proteins/genetics , Microscopy, Fluorescence , Movement , Organelles/metabolism , Plant Viral Movement Proteins , Protein Sorting Signals/genetics , Protein Sorting Signals/physiology , Protein Transport , Viral Proteins/genetics , Red Fluorescent Protein
10.
Virus Res ; 79(1-2): 145-52, 2001 Nov 05.
Article in English | MEDLINE | ID: mdl-11551655

ABSTRACT

The RNA1 of black currant reversion associated nepovirus (BRAV) is 7711 nucleotides (nt) long, excluding the poly-A tail, and contains one long open reading frame (ORF) which is translated into a polyprotein of 2094 amino acids. The 5' NTR of BRAV RNA1 is 66 nt long and 78% identical with RNA2 5' NTR only over the first 57 nucleotides. The 3' non-translated region (3'NTR) is 1360 nucleotides long, and after the first 24 nucleotides 95% identical with the 3'NTR of RNA2. RNA1 3'NTR contains several stretches, 694-24 nucleotides in length, which are 60-80% similar to corresponding areas of the other viruses of the subgroup c of nepoviruses (BLMV, CLRV, PRMV or TomRSV). The 2094 amino acids-long polypeptide encoded by BRAV RNA1 is 33% identical with that of PRMV between amino acids 9 and 2057, and has significant similarity also to those of other nepoviruses and comoviruses. Conserved amino acid motifs, characteristic for the viral protease co-factor, the NTP-binding protein, the cysteine protease and the RdRp core domains, known to occur in the polyproteins of different viruses of the picornavirus-like supergroup, are all detected in the amino acid sequences encoded by BRAV RNA1.


Subject(s)
Magnoliopsida/virology , Nepovirus/genetics , RNA, Viral/analysis , 3' Untranslated Regions , 5' Untranslated Regions , Amino Acid Sequence , Base Sequence , Molecular Sequence Data , Secoviridae/genetics
11.
Arch Virol ; 145(1): 51-61, 2000.
Article in English | MEDLINE | ID: mdl-10664405

ABSTRACT

A satellite RNA (satRNA) associated with blackcurrant reversion nepovirus (BRV) was isolated and its nucleotide sequence was determined from cDNA clones. BRV satRNA was 1432 nucleotides (nt) in length excluding the poly(A)-tail, and contained one open reading frame which encodes a polypeptide of 402 amino acids, with a calculated M(r) of 44 220. The coding region was bordered by a 5' leader sequence of 25 nt and a 3'-nontranslated region of 201 nt. Two in vitro translation products of approximately 45 kDa and 40 kDa were detected, indicating that two in-frame AUG codons at positions 26 and 134 may both be functional. Nucleotide sequence comparisons revealed a stretch of 865 nt that was 63% identical between BRV satRNA and the large satRNA of chicory yellow mottle nepovirus. A 5'-terminal consensus sequence and a 40 nt motif (located at positions 264-303 of BRV satRNA) were conserved between BRV satRNA and other nepoviral large satRNAs.


Subject(s)
Nepovirus/genetics , RNA, Satellite/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , DNA, Complementary/genetics , Molecular Sequence Data , Open Reading Frames , Protein Biosynthesis , RNA, Satellite/isolation & purification , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Viral Proteins/chemistry , Viral Proteins/genetics
12.
Virus Res ; 65(1): 87-92, 1999 Dec 01.
Article in English | MEDLINE | ID: mdl-10564755

ABSTRACT

The complete nucleotide sequence of blackcurrant reversion nepovirus (BRV) RNA2 was determined from cDNA clones. RNA2 was 6400 nucleotides (nt) in length excluding the 3' poly(A)-tail. It contained a single open reading frame of 4878 nts encoding a polypeptide of 1626 amino acids with a calculated M(r) of 178¿ omitted¿860. The genome organization of BRV RNA2 was similar to that of other nepoviruses, especially those with a large RNA2. The coat protein (CP) was located in the C-terminal region of the large polyprotein and contained amino acid motifs conserved among nepovirus CPs. Sequence comparisons revealed a proline (P) residue surrounded by hydrophobic amino acid residues located upstream of the CP. This P motif is conserved among the putative movement proteins of nepo-, como-, caulimo- and capilloviruses. An N-terminal domain of 350 amino acids of RNA2-encoded polyprotein shared 34 and 35% sequence identity with the N-terminal domains of tomato ringspot nepovirus RNA1- and RNA2-encoded polyproteins, respectively. Sequence identities between the N-terminal domains of BRV RNA2 and other nepoviral RNA2s were less than 20%; no common N-terminal motif was found.


Subject(s)
Genome, Viral , Magnoliopsida/virology , Nepovirus/genetics , RNA, Viral/analysis , Amino Acid Sequence , Cloning, Molecular , DNA, Complementary/genetics , Molecular Sequence Data , Sequence Homology, Amino Acid
13.
FEBS Lett ; 447(1): 121-3, 1999 Mar 19.
Article in English | MEDLINE | ID: mdl-10218595

ABSTRACT

Plant viruses move systemically from one leaf to another via phloem. However, the viral functions needed for systemic movement are not fully elucidated. An experimental system was designed to study the effects of low temperature on the vascular transport of the tobacco mosaic tobamovirus (TMV). Vascular transport of TMV from lower inoculated leaves to upper non-inoculated leaves via a stem segment kept at low temperature (4 degrees C) was not affected. On the other hand, several experiments were performed on tobacco leaves to demonstrate that virus replication did not occur at the same temperature. The data suggest that replication of TMV in the phloem of wild-type tobacco plants is not necessary for the vascular transport of TMV, and that the virus moves with photoassimilates as suggested previously.


Subject(s)
Plant Shoots/virology , Tobacco Mosaic Virus/growth & development , Tobacco Mosaic Virus/metabolism , Biological Transport , Cold Temperature , Plant Leaves/virology , Plant Stems/virology , Plants, Toxic , Nicotiana/virology , Virus Replication
14.
J Gen Virol ; 79 ( Pt 10): 2319-23, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9780035

ABSTRACT

The N-terminal P1 proteinase of potato virus Y (ordinary strain group isolate PVY-O) was expressed in E. coli. Antiserum was raised against the expressed protein and used to detect the viral proteins in infected tobacco leaf tissue by Western blotting and by electron microscopy with immunogold labelling. In the immunogold localization studies P1 protein was detected in association with the cytoplasmic inclusion bodies characteristic of PVY infections and in the cytoplasm of the infected plant cells. No significant P1 antibody binding with other plant cell organelles, or with the cell wall and plasmodesmata, was detected by immunogold labelling.


Subject(s)
Cytoplasm/virology , Inclusion Bodies/virology , Potyvirus/chemistry , Serine Endopeptidases/analysis , Solanum tuberosum/virology , Viral Proteins/analysis , Animals , Cytoplasm/chemistry , Immune Sera/immunology , Immunohistochemistry , Inclusion Bodies/chemistry , Rabbits , Serine Endopeptidases/immunology , Viral Proteins/immunology
15.
Virus Res ; 53(1): 1-11, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9617765

ABSTRACT

The nucleotide sequence of the 3' terminal 3105 nucleotides (nt) of RNA2 of blackcurrant reversion associated virus (BRAV), the first mite-transmitted member of the nepovirus group, has been determined. The sequence contains an open reading frame of 1744 nt in the virus-sense strand, a 3' untranslated region of 1360 nt and a 3' poly(A) tail. Analysis of the amino-terminal residues of purified coat protein (CP) suggests that the CP gene is located between nts 1361 and 2959 (from the 3' terminus) in the RNA2, and that Asp/Ser is the proteolytic cleavage site of CP in the RNA2 encoded polyprotein. The predicted translation product from the CP gene is a polypeptide of 533 amino acids with a calculated Mr of 57 561. The amino acid sequence of BRAV CP showed highest similarity to blueberry leaf mottle virus (BLMV), and tomato ringspot virus (ToRSV), two members of the proposed sub-group three of nepoviruses possessing large RNA2 components. Nucleic and amino acid sequence comparisons between BRAV CP and the CPs of other nepoviruses indicate that specific conserved nepovirus CP domains occur in the BRAV CP thus confirming that BRAV is a member of the subgroup three of nepoviruses. reserved.


Subject(s)
Capsid Proteins , Capsid/chemistry , Capsid/classification , Capsid/genetics , Mites/virology , Nepovirus/chemistry , Amino Acid Sequence , Animals , Base Sequence , Blotting, Northern , Cloning, Molecular , DNA, Complementary , Electrophoresis, Polyacrylamide Gel , Molecular Sequence Data , Nepovirus/genetics , Phylogeny , Restriction Mapping , Sequence Alignment , Sequence Analysis, DNA
17.
Phytopathology ; 87(4): 404-13, 1997 Apr.
Article in English | MEDLINE | ID: mdl-18945119

ABSTRACT

ABSTRACT Black currant reversion is a virus-like disease whose causal agent has not been identified. In rooted cuttings of a black currant plant affected with the severe form of the disease, pronounced chlorotic line patterns and ringspots developed in newly emerging leaves. From such symptom-bearing leaves, a virus was mechanically transmitted with difficulty to Chenopodium quinoa and, from this host, to other herbaceous test plants. The virus was purified and partially characterized, and the purified viri-ons were used for antiserum production. Virus particles were isometric, approximately 27 nm in diameter, and sedimented as two nucleoprotein components. They contained a protein species with a molecular mass of 55 kDa, which was readily degraded into a 54-kDa protein and two major RNA components of about 6,700 and 7,700 nucleotides (nt), each with a poly(A) tail. Most of these properties are shared by nepoviruses, but the virus was serologically unrelated to 14 nepoviruses or putative nepovi-ruses tested. However, the deduced sequence of 1,260 nt at the 3' end of one of the viral RNA species was distinct from any known viral sequence, except that it contained short regions of homology to the 3' terminal sequences of RNAs of seven other nepoviruses and two comovi-ruses. To detect this virus in Ribes plants, primers were designed from the known sequence to amplify a 210-nt region of the cDNA of the virus RNA using an immunocapture reverse transcriptase polymerase chain reaction (IC-RT-PCR) protocol. Using this assay for the virus, we associated its presence with two recognized forms of black currant reversion disease occurring in Finland, Scotland, or New Zealand. We also detected the virus in vector gall mites from reverted plants and in black currant plants on which such vector mites had fed. However, the virus was not detected by IC-RT-PCR in known healthy Ribes plants; in Ribes plants free from reversion, but affected by three other distinct virus-like diseases of Ribes; or in plants infected with arabis mosaic, strawberry latent ringspot, or raspberry ringspot nepoviruses. These data suggest that this virus may be the causal agent of reversion disease, and it is tentatively called black currant reversion associated virus.

18.
Proc Natl Acad Sci U S A ; 90(5): 2055-9, 1993 Mar 01.
Article in English | MEDLINE | ID: mdl-8446627

ABSTRACT

Alterations in the genomic position of the tobacco mosaic virus (TMV) genes encoding the 30-kDa cell-to-cell movement protein or the coat protein greatly affected their expression. Higher production of 30-kDa protein was correlated with increased proximity of the gene to the viral 3' terminus. A mutant placing the 30-kDa open reading frame 207 nucleotides nearer the 3' terminus produced at least 4 times the wild-type TMV 30-kDa protein level, while a mutant placing the 30-kDa open reading frame 470 nucleotides closer to the 3' terminus produced at least 8 times the wild-type TMV 30-kDa protein level. Increases in 30-kDa protein production were not correlated with the subgenomic mRNA promoter (SGP) controlling the 30-kDa gene, since mutants with either the native 30-kDa SGP or the coat protein SGP in front of the 30-kDa gene produced similar levels of 30-kDa protein. Lack of coat protein did not affect 30-kDa protein expression, since a mutant with the coat protein start codon removed did not produce increased amounts of 30-kDa protein. Effects of gene positioning on coat protein expression were examined by using a mutant containing two different tandemly positioned tobamovirus (TMV and Odontoglossum ringspot virus) coat protein genes. Only coat protein expressed from the gene positioned nearest the 3' viral terminus was detected. Analysis of 30-kDa and coat protein subgenomic mRNAs revealed no proportional increase in the levels of mRNA relative to the observed levels of 30-kDa and coat proteins. This suggests that a translational mechanism is primarily responsible for the observed effect of genomic position on expression of 30-kDa movement and coat protein genes.


Subject(s)
Capsid/genetics , Gene Expression Regulation, Viral , RNA, Viral/genetics , Tobacco Mosaic Virus/genetics , Viral Proteins/genetics , Cloning, Molecular , Genes, Viral , Plant Viral Movement Proteins , RNA, Messenger/genetics , Viral Structural Proteins/genetics
19.
Virology ; 175(1): 30-40, 1990 Mar.
Article in English | MEDLINE | ID: mdl-2309448

ABSTRACT

A series of tobacco mosaic virus (TMV)-hybrids containing a second 30K open reading frame (ORF) inserted into different positions of the genome 3' region were constructed. These insertional mutants were used to evaluate the effects of a modified viral genome organization on replication and gene expression. They were evaluated for stability upon systemic infection and subsequent host passage using RNase protection assays. A mutant with the second 30K ORF fused in frame to two-thirds of the coat protein reading frame replicated as a free-RNA virus and produced increased amounts of the hybrid protein compared to the wild-type 30K protein, but substantially reduced amounts compared to the wild-type coat protein. A mutant with the second 30K ORF inserted between the native 30K and coat protein ORFs produced reduced amounts of 30K protein but replicated efficiently and was maintained for weeks of systemic infection before the population gradually shifted to progeny wild-type TMV. Mutants with the second 30K ORF fused behind different lengths of the coat protein subgenomic RNA promoter/leader region and inserted between the coat protein gene and the 3' nontranslated sequences replicated poorly and the mutations were not maintained during continued replication in plants.


Subject(s)
Genes, Viral , Mutation , Tobacco Mosaic Virus/genetics , Base Sequence , Blotting, Western , Capsid/genetics , Gene Expression , Molecular Sequence Data , Molecular Weight , Plants, Toxic , RNA, Viral/genetics , RNA, Viral/isolation & purification , Restriction Mapping , Nicotiana/microbiology , Tobacco Mosaic Virus/physiology , Virus Replication
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