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Ia Ierley - One of the best experts on this subject based on the ideXlab platform.
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characterization of the stop codon readthrough signal of Colorado Tick Fever virus segment 9 rna
RNA, 2012Co-Authors: Sawsa Napthine, Christina Yek, Michael L Powell, Ia IerleyAbstract:Termination codon readthrough is utilized as a mechanism of expression of a growing number of viral and cellular proteins, but in many cases the mRNA signals that promote readthrough are poorly characterized. Here, we investigated the readthrough signal of Colorado Tick Fever virus (CTFV) segment 9 RNA (Seg-9). CTFV is the type-species of the genus Coltivirus within the family Reoviridae and is a Tick-borne, double-stranded, segmented RNA virus. Seg-9 encodes a 36-kDa protein VP9, and by readthrough of a UGA stop codon, a 65-kDa product, VP9′. Using a reporter system, we defined the minimal sequence requirements for readthrough and confirmed activity in both mammalian and insect cell-free translation systems, and in transfected mammalian cells. Mutational analysis revealed that readthrough was UGA specific, and that the local sequence context around the UGA influenced readthrough efficiency. Readthrough was also dependent upon a stable RNA stem–loop structure beginning eight bases downstream from the UGA codon. Mutational analysis of this stem–loop revealed a requirement for the stem region but not for substructures identified within the loop. Unexpectedly, we were unable to detect a ribosomal pause during translation of the CTFV signal, suggesting that the mechanism of readthrough, at least at this site, is unlikely to be dependent upon RNA secondary-structure induced ribosomal pausing at the recoded stop codon.
Houssam Attoui - One of the best experts on this subject based on the ideXlab platform.
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Complete nucleotide sequence of Colorado Tick Fever virus
2015Co-Authors: Segments M, Houssam Attoui, Xavier De LamballerieAbstract:The nucleotide sequences of the tenth (M6), eleventh (S1) and twelfth (S2) dsRNA genomic segments of the Florio strain (N-7180) of Colorado Tick Fever virus were determined and found to be 675, 998 and 1884 bp, respectively, in length. A nonanucleotide motif and a hexanucleotide motif were found to be highly conserved in the 5 « and 3« non-coding regions (NCRs), respectively, of the three segments. The first and last three nucleotides of each segment were of inverted complementarity, and segment-specific inverted terminal repeats were detected in the NCRs of the three segments. These findings suggest the occurrence of intra-cellular panhandle structures for the RNA tran-scripts. A readthrough phenomenon is suspected i
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SEROLOGIC AND MOLECULAR DIAGNOSIS OF Colorado Tick Fever VIRAL INFECTIONS
2015Co-Authors: Houssam Attoui, Frederique Billoir, Jean-marie Bruey, Philippe De Micco, De LamballerieAbstract:Abstract. Molecular and serologic methods usable for the biological diagnosis of Coltivirus infection are reported. We designed a multiplex reverse transcription–polymerase chain reaction system that allowed the simultaneous and specific amplification of three genomic segments from as little as 0.01 plaque-forming units. Another system in the S2 viral segment permitted the differential diagnosis of American and European viral isolates. We also discuss some improvements of previous ELISAs, and the results obtained with paired sera from Colorado Tick Fever (CTF) virus– infected individuals. Western blot analysis was developed that allowed the detection of antibodies to a 38-kD viral protein in all tested sera. It also enabled the detection of anti-CTF virus antibodies in ELISA-negative sera. Specific IgM antibodies against a synthetic viral peptide could be detected in sera at the acute stage of the infection. Together, these results should permit the diagnosis of Coltivirus infection at any stage of the pathology. Colorado Tick Fever (CTF) is a severe Tick-borne disease that is usually self-limited. This disease occurs in 11 western states in the United States and has also been reported in Canada.1 Yearly, 200–400 cases are reported throughout the endemic states in the United States.1,2 The clinical manifes-tations appear following the bite of the infected adult Rock
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Termination and read-through proteins encoded by genome segment 9 of Colorado Tick Fever virus.
Journal of General Virology, 2004Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, Xavier De LamballerieAbstract:Genome segment 9 (Seg-9) of Colorado Tick Fever virus (CTFV) is 1884 bp long and contains a large open reading frame (ORF; 1845 nt in length overall), although a single in-frame stop codon (at nt 1052-1054) reduces the ORF coding capacity by approximately 40 %. However, analyses of highly conserved RNA sequences in the vicinity of the stop codon indicate that it belongs to a class of 'leaky terminators'. The third nucleotide positions in codons situated both before and after the stop codon, shows the highest variability, suggesting that both regions are translated during virus replication. This also suggests that the stop signal is functionally leaky, allowing read-through translation to occur. Indeed, both the truncated 'termination' protein and the full-length 'read-through' protein (VP9 and VP9', respectively) were detected in CTFV-infected cells, in cells transfected with a plasmid expressing only Seg-9 protein products, and in the in vitro translation products from undenatured Seg-9 ssRNA. The ratios of full-length and truncated proteins generated suggest that read-through may be down-regulated by other viral proteins. Western blot analysis of infected cells and purified CTFV showed that VP9 is a structural component of the virion, while VP9' is a non-structural protein.
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Correspondence
2004Co-Authors: Xavier De Lamballerie, Houssam AttouiAbstract:genome segment 9 of Colorado Tick Fever viru
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Recombinant VP7-Based Enzyme-Linked Immunosorbent Assay for Detection of Immunoglobulin G Antibodies to Colorado Tick Fever Virus
Journal of Clinical Microbiology, 2003Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, Pierre Gallian, Philippe Biagini, Jean-françois Cantaloube, Xavier De LamballerieAbstract:VP6, VP7, VP9, VP10, VP11, and VP12 of Colorado Tick Fever virus (CTF virus), a virus member of the genus Coltivirus, family Reoviridae, were expressed in bacteria with the pGEX-4T-2 vector. A partial sequence of VP7 (designated pVP7) was chosen to elaborate an enzyme-linked immunosorbent assay (ELISA) for detecting anti-CTF virus immunoglobulin G (IgG) antibodies in humans. This was based on two observations: (i) among all expressed proteins, pVP7 showed the highest immunoreactivity to an anti-CTF virus hyperimmune ascitic fluid; (ii) to provide the highest selectivity of antibody detection, the expressed sequence was chosen within a region which is highly divergent (49% amino acid identity) from the homologous sequence of another coltivirus, the Eyach virus. The pVP7 ELISA was evaluated with 368 serum samples from French blood donors and found to provide 98.1% specificity. Assays with the Calisher set of human serum samples, positive for anti-CTF virus antibodies (C. H. Calisher, J. D. Poland, S. B. Calisher, and L. A Warmoth, J. Clin. Microbiol. 22:84-88, 1985), showed that the pVP7 ELISA provided 100% sensitivity for the tested population. After elaboration of recombinant-protein-based ELISAs for diagnosis of infections with members of the viral genera Orbivirus, Orthoreovirus, and Rotavirus, it was shown that a recombinant protein could be used to detect antibodies to the human pathogen Colorado Tick Fever virus.
Xavier De Lamballerie - One of the best experts on this subject based on the ideXlab platform.
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Complete nucleotide sequence of Colorado Tick Fever virus
2015Co-Authors: Segments M, Houssam Attoui, Xavier De LamballerieAbstract:The nucleotide sequences of the tenth (M6), eleventh (S1) and twelfth (S2) dsRNA genomic segments of the Florio strain (N-7180) of Colorado Tick Fever virus were determined and found to be 675, 998 and 1884 bp, respectively, in length. A nonanucleotide motif and a hexanucleotide motif were found to be highly conserved in the 5 « and 3« non-coding regions (NCRs), respectively, of the three segments. The first and last three nucleotides of each segment were of inverted complementarity, and segment-specific inverted terminal repeats were detected in the NCRs of the three segments. These findings suggest the occurrence of intra-cellular panhandle structures for the RNA tran-scripts. A readthrough phenomenon is suspected i
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Termination and read-through proteins encoded by genome segment 9 of Colorado Tick Fever virus.
Journal of General Virology, 2004Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, Xavier De LamballerieAbstract:Genome segment 9 (Seg-9) of Colorado Tick Fever virus (CTFV) is 1884 bp long and contains a large open reading frame (ORF; 1845 nt in length overall), although a single in-frame stop codon (at nt 1052-1054) reduces the ORF coding capacity by approximately 40 %. However, analyses of highly conserved RNA sequences in the vicinity of the stop codon indicate that it belongs to a class of 'leaky terminators'. The third nucleotide positions in codons situated both before and after the stop codon, shows the highest variability, suggesting that both regions are translated during virus replication. This also suggests that the stop signal is functionally leaky, allowing read-through translation to occur. Indeed, both the truncated 'termination' protein and the full-length 'read-through' protein (VP9 and VP9', respectively) were detected in CTFV-infected cells, in cells transfected with a plasmid expressing only Seg-9 protein products, and in the in vitro translation products from undenatured Seg-9 ssRNA. The ratios of full-length and truncated proteins generated suggest that read-through may be down-regulated by other viral proteins. Western blot analysis of infected cells and purified CTFV showed that VP9 is a structural component of the virion, while VP9' is a non-structural protein.
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Correspondence
2004Co-Authors: Xavier De Lamballerie, Houssam AttouiAbstract:genome segment 9 of Colorado Tick Fever viru
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Recombinant VP7-Based Enzyme-Linked Immunosorbent Assay for Detection of Immunoglobulin G Antibodies to Colorado Tick Fever Virus
Journal of Clinical Microbiology, 2003Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, Pierre Gallian, Philippe Biagini, Jean-françois Cantaloube, Xavier De LamballerieAbstract:VP6, VP7, VP9, VP10, VP11, and VP12 of Colorado Tick Fever virus (CTF virus), a virus member of the genus Coltivirus, family Reoviridae, were expressed in bacteria with the pGEX-4T-2 vector. A partial sequence of VP7 (designated pVP7) was chosen to elaborate an enzyme-linked immunosorbent assay (ELISA) for detecting anti-CTF virus immunoglobulin G (IgG) antibodies in humans. This was based on two observations: (i) among all expressed proteins, pVP7 showed the highest immunoreactivity to an anti-CTF virus hyperimmune ascitic fluid; (ii) to provide the highest selectivity of antibody detection, the expressed sequence was chosen within a region which is highly divergent (49% amino acid identity) from the homologous sequence of another coltivirus, the Eyach virus. The pVP7 ELISA was evaluated with 368 serum samples from French blood donors and found to provide 98.1% specificity. Assays with the Calisher set of human serum samples, positive for anti-CTF virus antibodies (C. H. Calisher, J. D. Poland, S. B. Calisher, and L. A Warmoth, J. Clin. Microbiol. 22:84-88, 1985), showed that the pVP7 ELISA provided 100% sensitivity for the tested population. After elaboration of recombinant-protein-based ELISAs for diagnosis of infections with members of the viral genera Orbivirus, Orthoreovirus, and Rotavirus, it was shown that a recombinant protein could be used to detect antibodies to the human pathogen Colorado Tick Fever virus.
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Sequence determination and analysis of the full-length genome of Colorado Tick Fever virus, the type species of genus Coltivirus (Family Reoviridae).
Biochemical and Biophysical Research Communications, 2000Co-Authors: Houssam Attoui, Frederique Billoir, Philippe De Micco, Philippe Biagini, Jean-françois Cantaloube, Reine De Chesse, Xavier De LamballerieAbstract:The Colorado Tick Fever virus (CTFV) is the type species of genus Coltivirus, family Reoviridae. Its genome consisting of 12 segments of dsRNA was completely sequenced. It was found to be 29,174 nucleotides long (the longest of all Reoviridae genomes characterized to date). Conserved sequences at the 5' end (SACUUUUGY) and at the 3' end (WUGCAGUS) of the 12 segments were identified. The analysis of the putative proteins deduced from the nucleotide sequences permitted to identify functional motifs. In particular, the VP1 was identified unambiguously as the viral RNA dependent RNA pylmerase (RDRP) (VP1pol), with a GDD located at a similar position to Reoviridae RDRPs. In other genes, RGD cell-binding, NTPAse, single strand binding protein and kinase motifs were identified. Comparison with Reoviridae proteins showed significant similarities to RDRPs (CTFV-VP1) and sigma C protein of orthoreovirus (CTFV-VP6). Similarities to nonviral enzymatic proteins, such as methyltransferases, NTPAses, RNA replication factors, were also identified.
Staplesj. Erin - One of the best experts on this subject based on the ideXlab platform.
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Colorado Tick Fever in the United States, 2002-2012.
Vector-Borne and Zoonotic Diseases, 2015Co-Authors: J Yendellstephanie, Fischermarc, Staplesj. ErinAbstract:Abstract Background: Colorado Tick Fever (CTF) is an acute systemic febrile illness caused by the CTF virus (CTFV). The last national summary of CTF cases in the United States included cases reported through 2001. This study summarizes national surveillance data for CTF from 2002 through 2012 and examines trends in the epidemiology and testing of identified CTF cases. Methods: Because CTF is not nationally notifiable, we identified CTF cases through solicited reports from state health departments and diagnostic laboratory records. For all cases, we collected data on age, sex, county of residence, travel history, symptom onset date, laboratory testing, and clinical outcome. Poisson regression was used to examine trends over time in case counts, and simple linear regression and logistic regression were used to examine trends in case characteristics. Results: From 2002 through 2012, 75 CTF cases were identified with a median of five cases per year (range 3–14). Forty-seven (63%) cases occurred in males and 4...
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Infection with Colorado Tick Fever virus among humans and Ticks in a national park and forest, Wyoming, 2010.
Vector-Borne and Zoonotic Diseases, 2014Co-Authors: L Geissleraimee, Thorpemily, Van Houtenclayton, S Lanciottirobert, Panellanicolas, L Cadwellbetsy, Murphytracy, Staplesj. ErinAbstract:Abstract Background: Colorado Tick Fever (CTF) is an underreported Tick-borne viral disease occurring in the western United States. CTF illness includes Fever, headache, and severe myalgia lasting for weeks. Wyoming has one of the highest CTF incidence rates with approximately 30% of infected persons reporting Tick exposure in a Wyoming National Park or Forest before symptom onset. We assessed CTF virus infections among humans and Dermacentor andersoni Ticks in Grand Teton National Park (GRTE) and Bridger-Teton National Forest (BTNF). Methods: In June of 2010, 526 eligible employees were approached to participate in a baseline and 3-month follow-up serosurvey and risk behavior survey. Seropositivity was defined as antibody titers against CTF virus ≥10, as measured by the plaque reduction neutralization test. Ticks were collected at 27 sites within GRTE/BTNF and tested by RT-PCR for the CTF virus. Results: A total of 126 (24%) employees participated in the baseline and follow-up study visits. Three (2%) em...
Sawsa Napthine - One of the best experts on this subject based on the ideXlab platform.
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characterization of the stop codon readthrough signal of Colorado Tick Fever virus segment 9 rna
RNA, 2012Co-Authors: Sawsa Napthine, Christina Yek, Michael L Powell, Ia IerleyAbstract:Termination codon readthrough is utilized as a mechanism of expression of a growing number of viral and cellular proteins, but in many cases the mRNA signals that promote readthrough are poorly characterized. Here, we investigated the readthrough signal of Colorado Tick Fever virus (CTFV) segment 9 RNA (Seg-9). CTFV is the type-species of the genus Coltivirus within the family Reoviridae and is a Tick-borne, double-stranded, segmented RNA virus. Seg-9 encodes a 36-kDa protein VP9, and by readthrough of a UGA stop codon, a 65-kDa product, VP9′. Using a reporter system, we defined the minimal sequence requirements for readthrough and confirmed activity in both mammalian and insect cell-free translation systems, and in transfected mammalian cells. Mutational analysis revealed that readthrough was UGA specific, and that the local sequence context around the UGA influenced readthrough efficiency. Readthrough was also dependent upon a stable RNA stem–loop structure beginning eight bases downstream from the UGA codon. Mutational analysis of this stem–loop revealed a requirement for the stem region but not for substructures identified within the loop. Unexpectedly, we were unable to detect a ribosomal pause during translation of the CTFV signal, suggesting that the mechanism of readthrough, at least at this site, is unlikely to be dependent upon RNA secondary-structure induced ribosomal pausing at the recoded stop codon.