scholarly journals Nora virus, a persistent virus in Drosophila, defines a new picorna-like virus family

2007 ◽  
Vol 88 (12) ◽  
pp. 3493-3493 ◽  
Author(s):  
Mazen S. Habayeb ◽  
Sophia K. Ekengren ◽  
Dan Hultmark
Keyword(s):  
Virus Family ◽  
Nora Virus ◽  
Persistent Virus

scholarly journals Nora virus, a persistent virus in Drosophila, defines a new picorna-like virus family

2006 ◽  
Vol 87 (10) ◽  
pp. 3045-3051 ◽  
Author(s):  
Mazen S. Habayeb ◽  
Sophia K. Ekengren ◽  
Dan Hultmark
Keyword(s):  
Persistent Infection ◽  
Open Reading Frames ◽  
Close Relative ◽  
Virus Family ◽  
Viral Genomes ◽  
Persistent Infections ◽  
New Family ◽  
Nora Virus ◽  
Persistent Virus ◽  
Viral Sequences

Several viruses, including picornaviruses, are known to establish persistent infections, but the mechanisms involved are poorly understood. Here, a novel picorna-like virus, Nora virus, which causes a persistent infection in Drosophila melanogaster, is described. It has a single-stranded, positive-sense genomic RNA of 11879 nt, followed by a poly(A) tail. Unlike other picorna-like viruses, the genome has four open reading frames (ORFs). One ORF encodes a picornavirus-like cassette of proteins for virus replication, including an iflavirus-like RNA-dependent RNA polymerase and a helicase that is related to those of mammalian picornaviruses. The three other ORFs are not closely related to any previously described viral sequences. The unusual sequence and genome organization in Nora virus suggest that it belongs to a new family of picorna-like viruses. Surprisingly, Nora virus could be detected in all tested D. melanogaster laboratory stocks, as well as in wild-caught material. The viral titres varied enormously, between 104 and 1010 viral genomes per fly in different stocks, without causing obvious pathological effects. The virus was also found in Drosophila simulans, a close relative of D. melanogaster, but not in more distantly related Drosophila species. It will now be possible to use Drosophila genetics to study the factors that control this persistent infection.

Arenaviruses

2011 ◽  
Author(s):  
Colin R. Howard
Keyword(s):  
South America ◽  
Lassa Fever ◽  
Lymphocytic Choriomeningitis ◽  
T Cell Response ◽  
Cytotoxic T Cell ◽  
Virus Infections ◽  
Virus Family ◽  
Adult Mice ◽  
Persistent Virus ◽  
Haemorrhagic Disease

There are few groups of viral zoonoses that have attracted such widespread publicity as the arenaviruses, particularly during the 1960’s and 1970’s when Lassa emerged as a major cause of haemorrhagic disease in West Africa. More than any other zoonoses, members of the family are used extensively for the study of virus-host relationships. Thus the study of this unique group of enveloped, single-stranded RNA viruses has been pursued for two quite separate reasons. First, lymphocytic choriomeningitis virus (LCM) has been used as a model of persistent virus infections for over half a century; its study has contributed, and continues to contribute, a number of cardinal concepts to our present understanding of immunology. LCM virus remains the prototype of the Arenaviridae and is a common infection of laboratory mice, rats and hamsters. Once thought rare in humans there is now increasing evidence of LCM virus being implicated in renal disease and as a complication in organ transplantation. Second, certain arenaviruses cause severe haemorrhagic diseases in man, notably Lassa fever in Africa, Argentine and Bolivian haemorrhagic fevers in South America, Guaranito infection in Venezuela and Chaparé virus in Bolivia. The latter is a prime example for the need of ever-continuing vigilance for the emergence of new viral diseases; over the past few years several new arenaviruses have been reported as implicated with severe human disease and indeed the number of new arenaviruses discovered since the last edition of this book have increased the size of this virus family significantly.In common with LCM, the natural reservoir of these infections is a limited number of rodent species (Howard, 1986). Although the initial isolates from South America were at first erroneously designated as newly defined arboviruses, there is no evidence to implicate arthropod transmission for any arenavirus. However, similar methods of isolation and the necessity of trapping small animals have meant that the majority of arenaviruses have been isolated by workers in the arbovirus field. A good example of this is Guaranito virus that emerged during investigation of a dengue virus outbreak in Venezuela (Salas et al. 1991).There is an interesting spectrum of pathological processes among these viruses. All the evidence so far available suggests that the morbidity of Lassa fever and South American haemorrhagic fevers due to arenavirus infection results from the direct cytopathic action of these agents. This is in sharp contrast to the immunopathological basis of ‘classic’ lymphocytic choriomeningitis disease seen in adult mice infected with LCM virus and the use of this system for elucidating the phenomenon of H2-restriction of the host cytotoxic T cell response (Zinkernagel and Doherty 1979). Despite the utility of this experimental model for dissecting the nature of the immune response to virus infection and the growing interest in arenaviruses of rodents, there remains much to be done to elucidate the pathogenesis of these infections in humans.

First Detection of Tobacco Mosaic Virus in Tobacco Fields in Northern Lebanon

2020 ◽  
Vol 20 ◽  
Author(s):  
Rami Obeid ◽  
Elias Wehbe ◽  
Mohamad Rima ◽  
Mohammad Kabara ◽  
Romeo Al Bersaoui ◽  
...  
Keyword(s):  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Viral Genome ◽  
Virus Genome ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Family ◽  
Crop Fields ◽  
Wide Range ◽  
Almost All ◽  
Das Elisa

Background: Tobacco mosaic virus (TMV) is the most known virus in the plant mosaic virus family and is able to infect a wide range of crops, in particularly tobacco, causing a production loss. Objectives: Herein, and for the first time in Lebanon, we investigated the presence of TMV infection in crops by analyzing 88 samples of tobacco, tomato, cucumber and pepper collected from different regions in North Lebanon. Methods: Double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), revealed a potential TMV infection of four tobacco samples out of 88 crops samples collected. However, no tomato, cucumber and pepper samples were infected. The TMV+ tobacco samples were then extensively analyzed by RT-PCR to detect viral RNA using different primers covering all the viral genome. Results and Discussion: PCR results confirmed those of DAS-ELISA showing TMV infection of four tobacco samples collected from three crop fields of North Lebanon. In only one of four TMV+ samples, we were able to amplify almost all the regions of viral genome, suggesting possible mutations in the virus genome or an infection with a new, not yet identified, TMV strain. Conclusion: Our study is the first in Lebanon revealing TMV infection in crop fields, and highlighting the danger that may affect the future of agriculture.

Coronavirus: history, genome structure and pathogenesis

Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Poonam B ◽  
Prabhjot Kaur Gill
Keyword(s):  
Genome Structure ◽  
Public Health Research ◽  
Replication Process ◽  
Virus Family ◽  
Enveloped Virus ◽  
Target Organs ◽  
Transcription Process ◽  
Recent Emergence ◽  
The Family ◽  
Discontinuous Transcription

Background: The positive sense and inordinate large RNA genome are enclosed by helical nuceocapsids along with an outermost layer belongs to the family Coronaviridae. The phylogenetic tree of this family has been quartered into Class1 as alpha, Class 2 as beta, Class 3 as gamma and Class 4 as delta CoV. The mammalian respiratory and gastrointestinal tracts are the main target organs of this enveloped virus with misperceived mechanisms. The relevance of this virus family has considerably increased by the dint of recent emergence of the Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS), which are caused by viruses belonging to the beta-CoV group. Aim: Aforesaid illustrations of emergence of coronavirus diseases over the past two decades, SARS (2002 and 2003) and MERS (2012 to present) - the ongoing COVID-19 outbreak has pressurized the WHO to take innovative measures for public health, research and medical communities. The aim of the present review is to have proficiency in coronavirus replication and transcription process which is still in its infancy. Conclusion: An outcome of epidemics, it is being recognized as one of the most advancing viruses by the virtue of high genomic nucleotide substitution rates and recombination. The hallmark of coronavirus replication is discontinuous transcription resulting in the production of multiple subgenomic mRNAs having sequences complementary to both ends of the genome. Therefore, complete genome sequence of coronavirus will be used as frame of reference for knowing this classical phenomenon of RNA replication process. Finally, research on the pathogenesis of coronaviruses and the host immunopathological response will aid in designing vaccines and minimizing mortality rate.

Multigene families in African swine fever virus: family 110.

1990 ◽  
Vol 64 (5) ◽  
pp. 2064-2072 ◽  
Author(s):  
J M Almendral ◽  
F Almazán ◽  
R Blasco ◽  
E Viñuela
Keyword(s):  
African Swine Fever Virus ◽  
African Swine Fever ◽  
Fever Virus ◽  
Multigene Families ◽  
Virus Family

scholarly journals Molecular Epidemiology and Whole-Genome Analysis of Bovine Foamy Virus in Japan

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1017
Author(s):  
Hirohisa Mekata ◽  
Tomohiro Okagawa ◽  
Satoru Konnai ◽  
Takayuki Miyazawa
Keyword(s):  
Phylogenetic Analyses ◽  
Foamy Virus ◽  
Pcr Analysis ◽  
Whole Genome ◽  
Genome Sequences ◽  
Whole Genome Analysis ◽  
Virus Family ◽  
Bovine Foamy Virus ◽  
Novel Genotype

Bovine foamy virus (BFV) is a member of the foamy virus family in cattle. Information on the epidemiology, transmission routes, and whole-genome sequences of BFV is still limited. To understand the characteristics of BFV, this study included a molecular survey in Japan and the determination of the whole-genome sequences of 30 BFV isolates. A total of 30 (3.4%, 30/884) cattle were infected with BFV according to PCR analysis. Cattle less than 48 months old were scarcely infected with this virus, and older animals had a significantly higher rate of infection. To reveal the possibility of vertical transmission, we additionally surveyed 77 pairs of dams and 3-month-old calves in a farm already confirmed to have BFV. We confirmed that one of the calves born from a dam with BFV was infected. Phylogenetic analyses revealed that a novel genotype was spread in Japan. In conclusion, the prevalence of BFV in Japan is relatively low and three genotypes, including a novel genotype, are spread in Japan.

scholarly journals Rotaviruses and Rotavirus Vaccines

Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 959
Author(s):  
Celeste M. Donato ◽  
Julie E. Bines
Keyword(s):  
Capsid Proteins ◽  
Virus Family ◽  
Rotavirus Vaccines ◽  
Group A Rotaviruses ◽  
Group A ◽  
Outer Capsid

Group A rotaviruses belong to the Reoviridae virus family and are classified into G and P genotypes based on the outer capsid proteins VP7 and VP4, respectively [...]

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