scholarly journals ICTV Virus Taxonomy Profile: Alphaflexiviridae

2020 ◽  
Vol 101 (7) ◽  
pp. 699-700 ◽  
Author(s):  
Jan F. Kreuze ◽  
Anna Maria Vaira ◽  
Wulf Menzel ◽  
Thierry Candresse ◽  
Sergey K. Zavriev ◽  
...  
Keyword(s):  
Triple Gene Block ◽  
International Committee ◽  
Replication Proteins ◽  
Virus Taxonomy ◽  
Long Distance ◽  
Gene Block ◽  
The Family ◽  
Single Exception ◽  
Distinct Lineage ◽  
Long Distance Movement

The family Alphaflexiviridae includes viruses with flexuous filamentous virions that are 470–800 nm in length and 12–13 nm in diameter. Alphaflexiviruses have a single-stranded, positive-sense RNA genome of 5.5–9 kb. They infect plants and plant-infecting fungi. They share a distinct lineage of alphavirus-like replication proteins that is unusual in lacking any recognized protease domain. With a single exception, cell-to-cell and long-distance movement is facilitated by triple gene block proteins in plant-infecting genera. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Alphaflexiviridae, which is available at www.ictv.global/report/alphaflexiviridae.

scholarly journals Varied Movement Strategies Employed by Triple Gene Block–Encoding Viruses

2010 ◽  
Vol 23 (10) ◽  
pp. 1231-1247 ◽  
Author(s):  
Jeanmarie Verchot-Lubicz ◽  
Lesley Torrance ◽  
Andrey G. Solovyev ◽  
Sergey Yu Morozov ◽  
Andrew O. Jackson ◽  
...  
Keyword(s):  
Protein Interactions ◽  
Rna Virus ◽  
Triple Gene Block ◽  
Cell Movement ◽  
Future Research ◽  
Subcellular Targeting ◽  
Long Distance ◽  
Movement Proteins ◽  
Gene Block ◽  
Long Distance Movement

Several RNA virus genera belonging to the Virgaviridae and Flexiviridae families encode proteins organized in a triple gene block (TGB) that facilitate cell-to-cell and long-distance movement. The TGB proteins have been traditionally classified as hordei-like or potex-like based on phylogenetic comparisons and differences in movement mechanisms of the Hordeivirus and Potexvirus spp. However, accumulating data from other model viruses suggests that a revised framework is needed to accommodate the profound differences in protein interactions occurring during infection and ancillary capsid protein requirements for movement. The goal of this article is to highlight common features of the TGB proteins and salient differences in movement properties exhibited by individual viruses encoding these proteins. We discuss common and divergent aspects of the TGB transport machinery, describe putative nucleoprotein movement complexes, highlight recent data on TGB protein interactions and topological properties, and review membrane associations occurring during subcellular targeting and cell-to-cell movement. We conclude that the existing models cannot be used to explain all TGB viruses, and we propose provisional Potexvirus, Hordeivirus, and Pomovirus models. We also suggest areas that might profit from future research on viruses harboring this intriguing arrangement of movement proteins.

scholarly journals Molecular Characterization of a Novel Wheat-infecting Virus in Family Betaflexiviridae

2021 ◽  
Author(s):  
Jianxiang Wu ◽  
Shuai Fu ◽  
Mengzhu He ◽  
Bingjian Sun ◽  
Xueping Zhou
Keyword(s):  
Triple Gene Block ◽  
International Committee ◽  
Open Reading Frames ◽  
Yellow Mosaic Virus ◽  
Wheat Yellow Mosaic Virus ◽  
Gene Block ◽  
Transmission Electron ◽  
The Family ◽  
Novel Virus

Abstract Wheat plants showing yellow mosaic in leaves and stunting were observed and collected from wheat fields in the Henan Province, China. Analyses of these plants through transmission electron microscopy showed that these plants contained two filamentous virus-like particles of 200–500 nm and 1000–1300 nm long, respectively. RNA-seq result unveiled a co-infection of wheat yellow mosaic virus (WYMV) and an unknown wheat-infecting virus. The complete genome sequence of the unknown virus is 8,410 nucleotide long, excluding its 3’ end poly (A) tail. This unknown virus has six open reading frames (ORFs). The ORF1 encodes a putative viral replication-associated protein, and the ORF2, 3 and 4 encode the triple gene block (TGB) proteins. The ORF5 and 6 encode the capsid protein (CP) and a protein with unknown function, respectively. Phylogenetic relationship analyses showed that this novel virus is evolutionarily related to viruses in the subfamily Quinvirinae, family Betaflexiviridae. It is, however, distinctly different from the viruses in other genera. Based on the species and genus demarcation criteria set by the International Committee on Taxonomy of Viruses (ICTV), we tentatively name this novel virus as wheat yellow stunt-associated betaflexivirus (WYSaBV). We also propose WYSaBV as a new member in a new genus in the family Betaflexiviridae.

scholarly journals Genomic Analyses of Cherry Rusty Mottle Group and Cherry Twisted Leaf-Associated Viruses Reveal a Possible New Genus Within the FamilyBetaflexiviridae

2015 ◽  
Vol 105 (3) ◽  
pp. 399-408 ◽  
Author(s):  
D. E. V. Villamor ◽  
J. Susaimuthu ◽  
K. C. Eastwell
Keyword(s):  
New Genus ◽  
High Throughput Sequencing ◽  
Prunus Avium ◽  
Triple Gene Block ◽  
Mottle Virus ◽  
Virus Species ◽  
Gene Block ◽  
Green Ring ◽  
The Family ◽  
Prunus Spp

It is demonstrated that closely related viruses within the family Betaflexiviridae are associated with a number of diseases that affect sweet cherry (Prunus avium) and other Prunus spp. Cherry rusty mottle-associated virus (CRMaV) is correlated with the appearance of cherry rusty mottle disease (CRMD), and Cherry twisted leaf-associated virus (CTLaV) is linked to cherry twisted leaf disease (CTLD) and apricot ringpox disease (ARPD). Comprehensive analysis of previously reported full genomic sequences plus those determined in this study representing isolates of CTLaV, CRMaV, Cherry green ring mottle virus, and Cherry necrotic rusty mottle virus revealed segregation of sequences into four clades corresponding to distinct virus species. High-throughput sequencing of RNA from representative source trees for CRMD, CTLD, and ARPD did not reveal additional unique virus sequences that might be associated with these diseases, thereby further substantiating the association of CRMaV and CTLaV with CRMD and CTLD or ARPD, respectively. Based on comparison of the nucleotide and amino acid sequence identity values, phylogenetic relationships with other triple-gene block-coding viruses within the family Betaflexiviridae, genome organization, and natural host range, a new genus (Robigovirus) is suggested.

scholarly journals A REVIEW PAPER ON POTATO MOP-TOP VIRUS (PMTV): OCCURRENCE, PROPERTIES AND MANAGEMENT

2016 ◽  
Vol 1 (3) ◽  
pp. 129 ◽  
Author(s):  
Aqleem Abbas ◽  
Meysam Madadi
Keyword(s):  
Coat Protein ◽  
Management Strategies ◽  
Triple Gene Block ◽  
Economic Losses ◽  
Tuber Quality ◽  
Potato Tubers ◽  
Long Distance ◽  
Gene Block ◽  
Potato Mop Top Virus ◽  
Important Disease

Potato mop-top virus (PMTV) is a plant pathogenic virus that affects potatoes. The virus was initially reported from Germany but now it has spread throughout Europe, Asia, South America and North America. It is responsible for spraing symptoms (brown arcs/lines, blemishes, and rings) on potato tubers and yellow chevrons or mopping (Shortened internodes) in the leaves and stems of plants grown from infected potato tubers. PMTV causes huge economic losses due to poor tuber quality. It is an important disease in the potato growing areas of the world. PMTV is tubular rod shape and has a single stranded positive sense RNA (+ssRNA) tripartite genome. RNA 1 encodes RdRp (viral RNA-dependent RNA polymerase). Coat protein (20kDa) and a larger protein (91kDa) is encoded by RNA2. RNA2 encodes larger protein (91 kDa) by read through (RT) of the amber termination codon of the coat protein. There are three conserved moldular sets of genes known as triple gene block (TGB) which are coded by RNA3. These TGBs are involved in cell to cell or long distance movement of PMTV. In nature, PMTV is vectored and transmitted by a soil born pathogen (Plasmodiophorid (Spongospora subterranean f.sp. subterranean abbreviated as ‘Sss’) that itself causes the powdery scab disease on tubers. The disease caused by PMTV and Sss are favored by cool and damp conditions. PMTV remain in spore balls of Sss for several years even if the potato is not grown in the field. There are no efficient means to manage the virus nor its vector in an infested field, therefore, preventive measures are essential. Since PMTV along with its vector is causing important disease of potato, so understanding its molecular, biological, physical properties and management strategies is very important.

scholarly journals ICTV Virus Taxonomy Profile: Ovaliviridae

2020 ◽  
Author(s):  
Li Huang ◽  
Haina Wang ◽  
Keyword(s):  
Viral Genome ◽  
International Committee ◽  
Virus Taxonomy ◽  
Enveloped Viruses ◽  
Content Type ◽  
Link Type ◽  
The Family ◽  
Virus Progeny ◽  
Linear Dsdna ◽  
Infected Cells

Ovaliviridae is a family of enveloped viruses with a linear dsDNA genome. The virions are ellipsoidal, and contain a multi-layered spool-like capsid. The viral genome is presumably replicated through protein priming by a putative DNA polymerase encoded by the virus. Progeny virions are released through hexagonal openings resulting from the rupture of virus-associated pyramids formed on the surface of infected cells. The only known host is a hyperthermophilic archaeon of the genus Sulfolobus . This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Ovaliviridae, which is available at ictv.global/report/ovaliviridae.

scholarly journals ICTV Virus Taxonomy Profile: Redondoviridae

2020 ◽  
Author(s):  
Arwa Abbas ◽  
Louis J. Taylor ◽  
Ronald G. Collman ◽  
Frederic D. Bushman ◽  
Keyword(s):  
Critical Illness ◽  
Causative Agent ◽  
Human Subjects ◽  
International Committee ◽  
Open Reading Frames ◽  
Metagenomic Sequencing ◽  
Virus Taxonomy ◽  
Single Stranded Dna ◽  
The Family ◽  
Reading Frames

Viruses in the family Redondoviridae have a circular genome of 3.0 kb with three open reading frames. The packaged genome is inferred to be single-stranded DNA by analogy to related viruses. Redondoviruses were discovered through metagenomic sequencing methods in samples from human subjects and are inferred to replicate in humans. Evidence of redondovirus infection is associated with periodontitis and critical illness, but redondoviruses have not been shown to be the causative agent of any diseases. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Redondoviridae, which is available at ictv.global/report/redondoviridae.

scholarly journals ICTV Virus Taxonomy Profile: Retroviridae 2021

2021 ◽  
Vol 102 (12) ◽  
Author(s):  
John Coffin ◽  
Jonas Blomberg ◽  
Hung Fan ◽  
Robert Gifford ◽  
Theodora Hatziioannou ◽  
...  
Keyword(s):  
Host Cell ◽  
Reverse Transcription ◽  
Viral Genome ◽  
Inner Core ◽  
Endogenous Retrovirus ◽  
International Committee ◽  
Virus Taxonomy ◽  
The Family ◽  
Vertebrate Hosts ◽  
Provirus Integration

Viruses in the family Retroviridae are found in a wide variety of vertebrate hosts. Enveloped virions are 80–100 nm in diameter with an inner core containing the viral genome and replicative enzymes. Core morphology is often characteristic for viruses within the same genus. Replication involves reverse transcription and integration into host cell DNA, resulting in a provirus. Integration into germline cells can result in a heritable provirus known as an endogenous retrovirus. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Retroviridae, which is available at ictv.global/report/retroviridae.

scholarly journals ICTV Virus Taxonomy Profile: Solemoviridae 2021

2021 ◽  
Vol 102 (12) ◽  
Author(s):  
Merike Sõmera ◽  
Denis Fargette ◽  
Eugénie Hébrard ◽  
Cecilia Sarmiento ◽  
Keyword(s):  
Host Range ◽  
Vegetative Propagation ◽  
International Committee ◽  
Insect Vectors ◽  
Virus Taxonomy ◽  
Mechanical Wounding ◽  
Narrow Host Range ◽  
The Family ◽  
Positive Sense ◽  
Polycistronic Rna

The family Solemoviridae includes viruses with icosahedral particles (26–34 nm in diameter) assembled on T=3 symmetry with a 4–6 kb positive-sense, monopartite, polycistronic RNA genome. Transmission of members of the genera Sobemovirus and Polemovirus occurs via mechanical wounding, vegetative propagation, insect vectors or abiotically through soil; members of the genera Polerovirus and Enamovirus are transmitted by specific aphids. Most solemoviruses have a narrow host range. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Solemoviridae, which is available at ictv.global/report/solemoviridae.

scholarly journals ICTV Virus Taxonomy Profile: Bornaviridae

2021 ◽  
Vol 102 (7) ◽  
Author(s):  
Dennis Rubbenstroth ◽  
Thomas Briese ◽  
Ralf Dürrwald ◽  
Masayuki Horie (堀江真行) ◽  
Timothy H. Hyndman ◽  
...  
Keyword(s):  
Public Health ◽  
Disease Virus ◽  
International Committee ◽  
Virus Taxonomy ◽  
Borna Disease Virus ◽  
Link Type ◽  
The Family ◽  
Rna Genome ◽  
Negative Sense ◽  
Borna Disease

Members of the family Bornaviridae produce enveloped virions containing a linear negative-sense non-segmented RNA genome of about 9 kb. Bornaviruses are found in mammals, birds, reptiles and fish. The most-studied viruses with public health and veterinary impact are Borna disease virus 1 and variegated squirrel bornavirus 1, both of which cause fatal encephalitis in humans. Several orthobornaviruses cause neurological and intestinal disorders in birds, mostly parrots. Endogenous bornavirus-like sequences occur in the genomes of various animals. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Bornaviridae, which is available at ictv.global/report/bornaviridae.

Sign in / Sign up

Export Citation Format

Share Document