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1.
Georgian Med News ; (300): 101-105, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32383711

RESUMO

Autoimmune Polyglandular Syndrome type 1 (APS-1) is a rare autoimmune disorder inherited in an autosomal recessive pattern. We present a clinical case of APS-1 in a 10-year-old child. The crux of this case was the lack of awareness to the disease and its complex flow, which resulted in complications during treatment. The progressive nature of the disease promoted further decline in child's condition. Moreover, there was an issue with mother's compliance, resulting in spontaneous and unwarranted drug cancelation.


Assuntos
Doenças Autoimunes , Poliendocrinopatias Autoimunes , Criança , Feminino , Humanos , Mães
2.
Georgian Med News ; (298): 119-122, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32141863

RESUMO

The aim of the research was to assess physical therapy effect using TRX equipment for patients after brain injuries, on balance and coordination. There were 30 respondents in this research. All of them with the easy level of brain injuries by using Glasgow coma scale. 10 females and 20 males, the age 19 - 64 years old, the average - 39,6±12,9 years. The coordination was assessed with no balance needed coordination scale by Schmitz. Balance using balance scale by Berg. The quality of life was assessed by using SF-36 questionnaire. Muscle strength by manual muscle strength scale by Lovett. Mathematical and statistical data analysis, using Microsoft Excel 2007 software package and SPSS 21.0. Data were statistically significant if p<0,05. The research lasted 15 days and consisted of daily training for 30-40 minutes. All respondents had two testing sessions, one before the first physical therapy with TRX class, and second after the last physical therapy with TRX class. Glasgow coma scale results showed that point ratio between the two groups was statistically insignificant (p>0,05). The mean of the study group points (14,7±0,45) was bigger than that of the control group (14,3±0,70). The muscle power results between two groups were statistically significant p<0,05 only in research group - 3,6±0,61 and 4,3±0,44, accordingly. Coordination assessment results showed that after physical therapy the results in the groups showed statistically significant improvement (p<0,05). The mean of the control group was 54,1±21,03, of the study group - 56,2±21,75. Quality of life and balance results for research subjects didn't change statistically significant, p>0,05. This brings to conclusion that TRX equipment is an important alternative to rehabilitation that improves patients' physical and emotional health after brain injuries.


Assuntos
Lesões Encefálicas Traumáticas/fisiopatologia , Lesões Encefálicas Traumáticas/reabilitação , Terapia por Exercício/métodos , Transtornos Neurológicos da Marcha/reabilitação , Treinamento Resistido/instrumentação , Adulto , Lesões Encefálicas Traumáticas/psicologia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Treinamento Resistido/métodos , Inquéritos e Questionários , Adulto Jovem
3.
Georgian Med News ; (291): 82-85, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31418736

RESUMO

Aim of the study - to assess the impact of physical therapy using musical elements, for Parkinson disease diagnosed people static and dynamic body balance thus psychological state. Research subjects were Parkinson disease diagnosed elderly people. Age 67-80 (67.5±12.5) years old, 9 men and 9 women, n=18. Research tools: Dynamic Gait Index (DGI) (Wrisley D., et al., 2003); Romberg's test - RT (Khasnis A, Gokula R.M, 2003); Burns Depression Checklist - BDC (Burns D., 2013). Microsoft Excel 2016, statistical significance level was set at p<0.05. BDC summarizing the research results, patients with PD tended to have less depression after the physical therapy with music elements sessions appliance. In terms of the DGI percentage decreased from 77.8% to 72.2% after physical therapy sessions. The evaluation of patients by RT, showed the positive results, compared in the beginning more than > 50 % of patients needed help or they could not complete the task. After classes - the percentage decreased. Patients static balance improved statistically significant.


Assuntos
Musicoterapia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Modalidades de Fisioterapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Marcha , Humanos , Masculino , Equilíbrio Postural
4.
J Virol ; 90(20): 9446-56, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27512068

RESUMO

UNLABELLED: We have previously shown that IFIT1 is primarily responsible for the antiviral action of interferon (IFN) alpha/beta against parainfluenza virus type 5 (PIV5), selectively inhibiting the translation of PIV5 mRNAs. Here we report that while PIV2, PIV5, and mumps virus (MuV) are sensitive to IFIT1, nonrubulavirus members of the paramyxoviridae such as PIV3, Sendai virus (SeV), and canine distemper virus (CDV) are resistant. The IFIT1 sensitivity of PIV5 was not rescued by coinfection with an IFIT1-resistant virus (PIV3), demonstrating that PIV3 does not specifically inhibit the antiviral activity of IFIT1 and that the inhibition of PIV5 mRNAs is regulated by cis-acting elements. We developed an in vitro translation system using purified human IFIT1 to further investigate the mechanism of action of IFIT1. While the translations of PIV2, PIV5, and MuV mRNAs were directly inhibited by IFIT1, the translations of PIV3, SeV, and CDV mRNAs were not. Using purified human mRNA-capping enzymes, we show biochemically that efficient inhibition by IFIT1 is dependent upon a 5' guanosine nucleoside cap (which need not be N7 methylated) and that this sensitivity is partly abrogated by 2'O methylation of the cap 1 ribose. Intriguingly, PIV5 M mRNA, in contrast to NP mRNA, remained sensitive to inhibition by IFIT1 following in vitro 2'O methylation, suggesting that other structural features of mRNAs may influence their sensitivity to IFIT1. Thus, surprisingly, the viral polymerases (which have 2'-O-methyltransferase activity) of rubulaviruses do not protect these viruses from inhibition by IFIT1. Possible biological consequences of this are discussed. IMPORTANCE: Paramyxoviruses cause a wide variety of diseases, and yet most of their genes encode structural proteins and proteins involved in their replication cycle. Thus, the amount of genetic information that determines the type of disease that paramyxoviruses cause is relatively small. One factor that will influence disease outcomes is how they interact with innate host cell defenses, including the interferon (IFN) system. Here we show that different paramyxoviruses interact in distinct ways with cells in a preexisting IFN-induced antiviral state. Strikingly, all the rubulaviruses tested were sensitive to the antiviral action of ISG56/IFIT1, while all the other paramyxoviruses tested were resistant. We developed novel in vitro biochemical assays to investigate the mechanism of action of IFIT1, demonstrating that the mRNAs of rubulaviruses can be directly inhibited by IFIT1 and that this is at least partially because their mRNAs are not correctly methylated.


Assuntos
Proteínas de Transporte/farmacologia , Paramyxoviridae/genética , Biossíntese de Proteínas/genética , RNA Mensageiro/genética , Rubulavirus/genética , Células A549 , Proteínas Adaptadoras de Transdução de Sinal , Linhagem Celular Tumoral , Humanos , Interferon-alfa/metabolismo , Metilação , Vírus da Caxumba/genética , Vírus da Parainfluenza 5/genética , Capuzes de RNA/genética , RNA Viral/genética , Proteínas de Ligação a RNA , Vírus Sendai/genética , Replicação Viral/genética
5.
J Gen Virol ; 94(Pt 1): 59-68, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23052390

RESUMO

Interferon (IFN) induces an antiviral state in cells that results in alterations of the patterns and levels of parainfluenza virus type 5 (PIV5) transcripts and proteins. This study reports that IFN-stimulated gene 56/IFN-induced protein with tetratricopeptide repeats 1 (ISG56/IFIT1) is primarily responsible for these effects of IFN. It was shown that treating cells with IFN after infection resulted in an increase in virus transcription but an overall decrease in virus protein synthesis. As there was no obvious decrease in the overall levels of cellular protein synthesis in infected cells treated with IFN, these results suggested that ISG56/IFIT1 selectively inhibits the translation of viral mRNAs. This conclusion was supported by in vitro translation studies. Previous work has shown that ISG56/IFIT1 can restrict the replication of viruses lacking a 2'-O-methyltransferase activity, an enzyme that methylates the 2'-hydroxyl group of ribose sugars in the 5'-cap structures of mRNA. However, the data in the current study strongly suggested that PIV5 mRNAs are methylated at the 2'-hydroxyl group and thus that ISG56/IFIT1 selectively inhibits the translation of PIV5 mRNA by some as yet unrecognized mechanism. It was also shown that ISG56/IFIT1 is primarily responsible for the IFN-induced inhibition of PIV5.


Assuntos
Proteínas de Transporte/biossíntese , Interferon-alfa/farmacologia , Infecções por Respirovirus/virologia , Respirovirus/efeitos dos fármacos , Respirovirus/genética , Proteínas Virais/biossíntese , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Replicação do DNA , Técnicas de Silenciamento de Genes , Humanos , Interferon alfa-2 , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , Proteínas de Ligação a RNA , Proteínas Recombinantes/farmacologia , Respirovirus/metabolismo , Infecções por Respirovirus/tratamento farmacológico , Infecções por Respirovirus/metabolismo , Transcrição Gênica , Células Vero , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
6.
J Gen Virol ; 90(Pt 11): 2731-2738, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19625458

RESUMO

Although the Enders strain of mumps virus (MuV) encodes a functional V protein that acts as an interferon (IFN) antagonist, in multi-cycle growth assays MuV Enders grew poorly in naïve ('IFN-competent' Hep2) cells but grew to high titres in 'IFN-compromised' Hep2 cells. Even so, the growth rate of MuV Enders was significantly slower in 'IFN-compromised' Hep2 cells when compared with its replication rate in Vero cells and with the replication rate of parainfluenza virus type 5 (a closely related paramyxovirus) in both naïve and 'IFN-compromised' Hep2 cells. This suggests that a consequence of slower growth is that the IFN system of naïve Hep2 cells can respond quickly enough to control the growth of MuV Enders. This is supported by the finding that rapidly growing variants of MuV Enders that were selected on 'IFN-compromised' Hep2 cells (i.e. in the absence of any selection pressure exerted by the IFN response) also grew to high titres on naïve Hep2 cells. Sequencing of the complete genome of one of these variants identified a single point mutation that resulted in a substitution of a conserved asparagine by histidine at position 498 of the haemagglutinin-neuraminidase protein, although this mutation was not present in all rapidly growing variants. These results support the concept that there is a race between the ability of a cell to detect and respond to virus infection and the ability of a virus to block the IFN response. Importantly, this emphasizes that factors other than viral IFN antagonists influence the sensitivity of viruses to IFN.


Assuntos
Interferons/antagonistas & inibidores , Interferons/imunologia , Vírus da Caxumba/imunologia , Vírus da Caxumba/fisiologia , Replicação Viral , Substituição de Aminoácidos/genética , Animais , Linhagem Celular , Chlorocebus aethiops , Análise Mutacional de DNA , Proteína HN/genética , Humanos , Mutação de Sentido Incorreto , Ensaio de Placa Viral
7.
J Virol ; 83(3): 1465-73, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19019954

RESUMO

The RNA helicases encoded by melanoma differentiation-associated gene 5 (mda-5) and retinoic acid-inducible gene I (RIG-I) detect foreign cytoplasmic RNA molecules generated during the course of a virus infection, and their activation leads to induction of type I interferon synthesis. Paramyxoviruses limit the amount of interferon produced by infected cells through the action of their V protein, which binds to and inhibits mda-5. Here we show that activation of both mda-5 and RIG-I by double-stranded RNA (dsRNA) leads to the formation of homo-oligomers through self-association of the helicase domains. We identify a region within the helicase domain of mda-5 that is targeted by all paramyxovirus V proteins and demonstrate that they inhibit activation of mda-5 by blocking dsRNA binding and consequent self-association. In addition to this commonly targeted domain, some paramyxovirus V proteins target additional regions of mda-5. In contrast, V proteins cannot bind to RIG-I and consequently have no effect on the ability of RIG-I to bind dsRNA or to form oligomers.


Assuntos
RNA Helicases DEAD-box/antagonistas & inibidores , Paramyxoviridae/fisiologia , Proteínas Virais/fisiologia , Animais , Biopolímeros , Linhagem Celular , Chlorocebus aethiops , RNA Helicases DEAD-box/metabolismo , Humanos , Hidrólise , Helicase IFIH1 Induzida por Interferon , Técnicas do Sistema de Duplo-Híbrido , Células Vero
8.
Proc Natl Acad Sci U S A ; 101(49): 17264-9, 2004 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-15563593

RESUMO

Most paramyxoviruses circumvent the IFN response by blocking IFN signaling and limiting the production of IFN by virus-infected cells. Here we report that the highly conserved cysteine-rich C-terminal domain of the V proteins of a wide variety of paramyxoviruses binds melanoma differentiation-associated gene 5 (mda-5) product. mda-5 is an IFN-inducible host cell DExD/H box helicase that contains a caspase recruitment domain at its N terminus. Overexpression of mda-5 stimulated the basal activity of the IFN-beta promoter in reporter gene assays and significantly enhanced the activation of the IFN-beta promoter by intracellular dsRNA. Both these activities were repressed by coexpression of the V proteins of simian virus 5, human parainfluenza virus 2, mumps virus, Sendai virus, and Hendra virus. Similar results to the reporter assays were obtained by measuring IFN production. Inhibition of mda-5 by RNA interference or by dominant interfering forms of mda-5 significantly inhibited the activation of the IFN-beta promoter by dsRNA. It thus appears that mda-5 plays a central role in an intracellular signal transduction pathway that can lead to the activation of the IFN-beta promoter, and that the V proteins of paramyxoviruses interact with mda-5 to block its activity.


Assuntos
Interferon beta/genética , Paramyxoviridae/química , RNA Helicases/antagonistas & inibidores , Ativação Transcricional/efeitos dos fármacos , Proteínas Virais/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , RNA Helicases DEAD-box , Humanos , Helicase IFIH1 Induzida por Interferon , Regiões Promotoras Genéticas/efeitos dos fármacos , Ligação Proteica , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Interferente Pequeno/farmacologia , Transdução de Sinais , Transfecção , Proteínas Virais/genética , Proteínas Virais/farmacologia
9.
J Gen Virol ; 85(Pt 10): 3007-3016, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15448364

RESUMO

Sequence comparison of the V/P and F genes of 13 human, canine, porcine and simian isolates of simian virus 5 (SV5) revealed a surprising lack of sequence variation at both the nucleotide and amino acid levels (0-3%), even though the viruses were isolated over 30 years and originated from countries around the world. Furthermore, there were no clear distinguishing amino acid or nucleotide differences among the isolates that correlated completely with the species from which they were isolated. In addition, there was no evidence that the ability of the viruses to block interferon signalling by targeting STAT1 for degradation was confined to the species from which they were isolated. All isolates had an extended cytoplasmic tail in the F protein, compared with the original W3A and WR monkey isolates. Sequence analysis of viruses that were derived from human bone-marrow cells isolated in London in the 1980s revealed that, whilst they were related more closely to one another than to the other isolates, they all had identifying differences, suggesting that they were independent isolates. These results therefore support previous data suggesting that SV5 can infect humans persistently, although the relationship of SV5 to any human disease remains highly contentious. Given that SV5 has been isolated on multiple occasions from different species, it is proposed that the term simian virus 5 is inappropriate and suggested that the virus should be renamed parainfluenza virus 5.


Assuntos
Chlorocebus aethiops/virologia , Cães/virologia , Vírus da Parainfluenza 5/classificação , Suínos/virologia , Sequência de Aminoácidos , Animais , Proteínas de Ligação a DNA/metabolismo , Humanos , Dados de Sequência Molecular , Filogenia , Fator de Transcrição STAT1 , Transativadores/metabolismo , Células Vero
10.
J Virol ; 76(22): 11379-86, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12388698

RESUMO

The V protein of simian virus 5 (SV5) blocks interferon signaling by targeting STAT1 for proteasome-mediated degradation. Here we present three main pieces of evidence which demonstrate that the p127 subunit (DDB1) of the UV damage-specific DNA binding protein (DDB) plays a central role in this degradation process. First, the V protein of an SV5 mutant which fails to target STAT1 for degradation does not bind DDB1. Second, mutations in the N and C termini of V which abolish the binding of V to DDB1 also prevent V from blocking interferon (IFN) signaling. Third, treatment of HeLa/SV5-V cells, which constitutively express the V protein of SV5 and thus lack STAT1, with short interfering RNAs specific for DDB1 resulted in a reduction in DDB1 levels with a concomitant increase in STAT1 levels and a restoration of IFN signaling. Furthermore, STAT1 is degraded in GM02415 (2RO) cells, which have a mutation in DDB2 (the p48 subunit of DDB) which abolishes its ability to interact with DDB1, thereby demonstrating that the role of DDB1 in STAT1 degradation is independent of its association with DDB2. Evidence is also presented which demonstrates that STAT2 is required for the degradation of STAT1 by SV5. These results suggest that DDB1, STAT1, STAT2, and V may form part of a large multiprotein complex which leads to the targeted degradation of STAT1 by the proteasome.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Rubulavirus/patogenicidade , Transativadores/metabolismo , Proteínas Virais , Proteínas Estruturais Virais/metabolismo , Animais , Linhagem Celular , Células HeLa , Humanos , Interferons/metabolismo , Vírus da Parainfluenza 2 Humana/patogenicidade , Vírus da Parainfluenza 2 Humana/fisiologia , Rubulavirus/fisiologia , Fator de Transcrição STAT1 , Fator de Transcrição STAT2 , Transdução de Sinais , Replicação Viral , Xeroderma Pigmentoso/metabolismo
11.
Virology ; 293(2): 234-42, 2002 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11886243

RESUMO

CPI(+) and CPI(-) are two canine isolates of simian virus 5 (SV5). CPI(+) was originally isolated from the cerebrospinal fluid of a dog with temporary posterior paralysis and CPI(-) was recovered at 12 days p.i. from the brain tissue of a dog experimentally infected with CPI(+). We have previously shown that the V protein of SV5 blocks interferon (IFN) signalling by targeting STAT1 for degradation. Here we report that whilst CPI(+) targets STAT1 for degradation, CPI(-) fails to and as a consequence, CPI(+) blocks IFN signalling but CPI(-) does not. Three amino acid differences in the P/V N-terminal common domain of the V protein are responsible for the observed difference in the abilities of CPI(+) and CPI(-) to block IFN signalling. In cells persistently infected with CPI(-) the virus may become repressed in response to IFN, under which circumstances virus glycoproteins are lost from the surface of infected cells and virus nucleocapsid proteins accumulate in cytoplasmic inclusion bodies. We suggest that in vivo cells infected with IFN-resistant viruses (in which there would be continuous virus protein synthesis) may be more susceptible to killing by cytotoxic T cells than cells infected with IFN-sensitive viruses (in which virus protein synthesis was repressed), and a model of virus persistence is put forward in which there is alternating selection of IFN-resistant and IFN-sensitive viruses depending upon the state of the adaptive immune response.


Assuntos
Interferon Tipo I/farmacologia , Paramyxoviridae/fisiologia , Transdução de Sinais , Substituição de Aminoácidos , Animais , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Cães , Humanos , Camundongos , Paramyxoviridae/metabolismo , Proteínas Recombinantes , Fator de Transcrição STAT1 , Especificidade da Espécie , Transativadores/metabolismo , Proteínas Estruturais Virais/química , Proteínas Estruturais Virais/metabolismo
12.
J Virol ; 76(5): 2159-67, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11836393

RESUMO

Human cell lines were isolated that express the V protein of either simian virus 5 (SV5) or human parainfluenza virus type 2 (hPIV2); the cell lines were termed 2f/SV5-V and 2f/PIV2-V, respectively. STAT1 was not detectable in 2f/SV5-V cells, and the cells failed to signal in response to either alpha/beta interferons (IFN-alpha and IFN-beta, or IFN-alpha/beta) or gamma interferon (IFN-gamma). In contrast, STAT2 was absent from 2f/PIV2-V cells, and IFN-alpha/beta but not IFN-gamma signaling was blocked in these cells. Treatment of both 2f/SV5-V and 2f/PIV2-V cells with a proteasome inhibitor allowed the respective STAT levels to accumulate at rates similar to those seen in 2fTGH cells, indicating that the V proteins target the STATs for proteasomal degradation. Infection with SV5 can lead to a complete loss of both phosphorylated and nonphosphorylated forms of STAT1 by 6 h postinfection. Since the turnover of STAT1 in uninfected cells is longer than 24 h, we conclude that degradation of STAT1 is the main mechanism by which SV5 blocks interferon (IFN) signaling. Pretreatment of 2fTGH cells with IFN-alpha severely inhibited both SV5 and hPIV2 protein synthesis. However, and in marked contrast, pretreatment of 2fTGH cells with IFN-gamma had little obvious effect on SV5 protein synthesis but did significantly reduce the replication of hPIV2. Pretreament with IFN-alpha or IFN-gamma did not induce an antiviral state in 2f/SV5-V cells, indicating either that the induction of an antiviral state is completely dependent on STAT signaling or that the V protein interferes with other, STAT-independent cell signaling pathways that may be induced by IFNs. Even though SV5 blocked IFN signaling, the addition of exogenous IFN-alpha to the culture medium of 2fTGH cells 12 h after a low-multiplicity infection with SV5 significantly reduced the subsequent cell-to-cell spread of virus. The significance of the results in terms of the strategy that these viruses have evolved to circumvent the IFN response is discussed.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Vírus da Parainfluenza 2 Humana/fisiologia , Rubulavirus/fisiologia , Transativadores/metabolismo , Proteínas Estruturais Virais/metabolismo , Animais , Antivirais/farmacologia , Divisão Celular , Linhagem Celular , Clonagem Molecular , Humanos , Interferons/farmacologia , Vírus da Parainfluenza 2 Humana/efeitos dos fármacos , Rubulavirus/efeitos dos fármacos , Fator de Transcrição STAT1 , Fator de Transcrição STAT2 , Transfecção , Raios Ultravioleta , Proteínas Virais/metabolismo , Proteínas Estruturais Virais/genética , Replicação Viral
13.
J Gen Virol ; 80 ( Pt 5): 1133-1139, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10355759

RESUMO

Amino acid differences between helper component-proteinase (HC-Pro) and coat protein (CP) that are putatively associated with biological differences between isolates PVA-B11 and PVA-U of potato A potyvirus (PVA) were studied using an infectious cDNA clone of PVA-B11. Replacement of the entire CP gene of PVA-B11 with the CP gene of PVA-U reduced virus accumulation in tobacco 5-fold, to the level of PVA-U. In contrast, four simultaneous amino acid substitutions made in PVA-B11 HC-Pro (according to PVA-U HC-Pro) increased virus accumulation 2- to 4-fold. A single substitution (S7G) at the CP N terminus reduced virus accumulation 10-fold, but restored aphid-transmissibility of PVA-B11. Simultaneous mutation of HC-Pro and replacement of CP in B11 delayed systemic movement in tobacco and limited cell-to-cell movement in potato. These results imply coordinated functions of HC-Pro and CP in accumulation and movement of PVA, because the phenotypic effects caused by simultaneous mutation of the two genes were different from the expected 'sum' of phenotypic changes observed following mutation of only one gene at a time.


Assuntos
Capsídeo/metabolismo , Cisteína Endopeptidases/metabolismo , Nicotiana/virologia , Plantas Tóxicas , Potyvirus/fisiologia , Solanum tuberosum/virologia , Proteínas Virais/metabolismo , Substituição de Aminoácidos , Antígenos Virais/análise , Capsídeo/química , Capsídeo/genética , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Ensaio de Imunoadsorção Enzimática , Genes Virais , Mutação , Doenças das Plantas/virologia , Potyvirus/imunologia , Nicotiana/imunologia , Proteínas Virais/química , Proteínas Virais/genética
14.
Phytopathology ; 88(4): 311-21, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18944954

RESUMO

ABSTRACT Sequences of the coat protein (CP) and 3'-end nontranslated region (3'NTR) of 13 isolates and the helper component proteinase (HC) of nine isolates of potato A potyvirus (PVA) were determined and compared with the eight previously determined PVA CP and 3'NTR sequences and one HC sequence. CP amino acid (aa), 3'NTR nucleotide, and HC aa sequence identities were 92.9, 93.4, and 94.8%, respectively. Sequence data, serological tests, and the necrotic local lesions induced in the leaves of the potato hybrid 'A6' confirmed that tamarillo mosaic virus is a strain of PVA. The aa substitutions A6T and G7S in the CP N-terminus were correlated with loss of aphid transmissibility. Development of necrotic lesions or nonnecrotic symptoms in the systemically infected leaves or lack of systemic spread in potato cv. King Edward were used to place the PVA isolates into four strain groups, but this grouping was not correlated with any differences in CP, HC, or 3'NTR. Recognition of CP by three monoclonal antibodies was used to place the PVA isolates into three groups different from the four groups above. The epitopes of two mono-clonal antibodies were mapped by site-directed mutagenesis to the same lysine residue at the CP aa 34.

15.
Arch Virol ; 141(7): 1207-19, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8774682

RESUMO

The sequences of the 3'-terminal 1145 nucleotides of two non-aphid transmissible (NAT) isolates (Ali and Juliniere) and one aphid transmissible (AT) isolate (Rouge) of potato virus A (PVA) RNA were determined. Those sequences contained the complete coding region of the coat protein (CP) followed by a 3'-nontranslated region (3'-NTR) of 225 (Ali and Juliniere) and 227 (Rouge) nucleotides. The obtained sequences were compared to those of the 3'-regions of four published PVA isolates and a virus described as tamarillo mosaic virus (TamMV) which on the basis of sequence data is a strain of PVA. The analysis of the 3'-terminal region of PVA isolates indicated that the CP N-terminal variable domain (32 residues) divides PVA isolates into two subgroups, where only tripeptide DAG correlates with aphid transmissibility. In addition to DAG/DAS sequence we found four other amino acids at the N-terminus of PVA CP, which are conserved in two subgroups. The central region (core part and C-termini) of CP is highly conserved among all PVA isolates (96.6 to 99.6%). 3'-NTR, separates PVA-isolates into two subgroups on the basis of its length and homology.


Assuntos
Capsídeo/genética , Potyvirus/genética , RNA Viral/química , Solanum tuberosum/virologia , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/química , Dados de Sequência Molecular
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