scholarly journals ICTV Virus Taxonomy Profile: Herpesviridae 2021

2021 ◽  
Vol 102 (10) ◽  
Author(s):  
Derek Gatherer ◽  
Daniel P. Depledge ◽  
Carol A. Hartley ◽  
Moriah L. Szpara ◽  
Paola K. Vaz ◽  
...  
Keyword(s):  
Latent Infection ◽  
Severe Disease ◽  
Viral Gene Expression ◽  
International Committee ◽  
Viral Gene ◽  
Complex Structures ◽  
Virus Taxonomy ◽  
Double Stranded Dna ◽  
The Family ◽  
Reptilian Species

Members of the family Herpesviridae have enveloped, spherical virions with characteristic complex structures consisting of symmetrical and non-symmetrical components. The linear, double-stranded DNA genomes of 125–241 kbp contain 70–170 genes, of which 43 have been inherited from an ancestral herpesvirus. In general, herpesviruses have coevolved with and are highly adapted to their hosts, which comprise many mammalian, avian and reptilian species. Following primary infection, they are able to establish lifelong latent infection, during which there is limited viral gene expression. Severe disease is usually observed only in the foetus, the very young, the immunocompromised or following infection of an alternative host. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Herpesviridae, which is available at ictv.global/report/herpesviridae.

scholarly journals ICTV Virus Taxonomy Profile: Hepadnaviridae

2020 ◽  
Vol 101 (6) ◽  
pp. 571-572 ◽  
Author(s):  
Lars Magnius ◽  
William S. Mason ◽  
John Taylor ◽  
Michael Kann ◽  
Dieter Glebe ◽  
...  
Keyword(s):  
Reverse Transcription ◽  
Family Members ◽  
International Committee ◽  
Virus Taxonomy ◽  
Enveloped Viruses ◽  
Link Type ◽  
Double Stranded Dna ◽  
The Family

The family Hepadnaviridae comprises small enveloped viruses with a partially double-stranded DNA genome of 3.0–3.4 kb. All family members express three sets of proteins (preC/C, polymerase and preS/S) and replication involves reverse transcription within nucleocapsids in the cytoplasm of hepatocytes. Hepadnaviruses are hepatotropic and infections may be transient or persistent. There are five genera: Parahepadnavirus, Metahepadnavirus, Herpetohepadnavirus, Avihepadnavirus and Orthohepadnavirus. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Hepadnaviridae, which is available at ictv.global/report/hepadnaviridae.

scholarly journals ICTV Virus Taxonomy Profile: Portogloboviridae

2021 ◽  
Vol 102 (6) ◽  
Author(s):  
David Prangishvili ◽  
Ying Liu ◽  
Mart Krupovic ◽  
Keyword(s):  
International Committee ◽  
Hyperthermophilic Archaea ◽  
Virus Taxonomy ◽  
Lipid Layer ◽  
Content Type ◽  
Link Type ◽  
Double Stranded Dna ◽  
The Family ◽  
Protein Shell

Portogloboviridae is a family of viruses with circular, double-stranded DNA genomes of about 20 kbp. Their icosahedral virions have a diameter of 87 nm, and consist of an outer protein shell, an inner lipid layer and a nucleoprotein core wound up into a spherical coil. Portogloboviruses infect hyperthermophilic archaea of the genus Saccharolobus , order Sulfolobales and are presumably nonlytic. Portogloboviruses encode mini-CRISPR arrays which they use to compete against other co-infecting viruses. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Portogloboviridae, which is available at ictv.global/report/portogloboviridae.

scholarly journals Herpesviral Latency—Common Themes

Pathogens ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 125 ◽  
Author(s):  
Magdalena Weidner-Glunde ◽  
Ewa Kruminis-Kaszkiel ◽  
Mamata Savanagouder
Keyword(s):  
Cell Biology ◽  
Particle Production ◽  
Viral Gene Expression ◽  
Lytic Cycle ◽  
Latent Reservoir ◽  
Viral Gene ◽  
Target Cells ◽  
Viral Particle Production ◽  
The Family ◽  
The Common

Latency establishment is the hallmark feature of herpesviruses, a group of viruses, of which nine are known to infect humans. They have co-evolved alongside their hosts, and mastered manipulation of cellular pathways and tweaking various processes to their advantage. As a result, they are very well adapted to persistence. The members of the three subfamilies belonging to the family Herpesviridae differ with regard to cell tropism, target cells for the latent reservoir, and characteristics of the infection. The mechanisms governing the latent state also seem quite different. Our knowledge about latency is most complete for the gammaherpesviruses due to previously missing adequate latency models for the alpha and beta-herpesviruses. Nevertheless, with advances in cell biology and the availability of appropriate cell-culture and animal models, the common features of the latency in the different subfamilies began to emerge. Three criteria have been set forth to define latency and differentiate it from persistent or abortive infection: 1) persistence of the viral genome, 2) limited viral gene expression with no viral particle production, and 3) the ability to reactivate to a lytic cycle. This review discusses these criteria for each of the subfamilies and highlights the common strategies adopted by herpesviruses to establish latency.

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.

ICTV Virus Taxonomy Profile: Nyamiviridae 2021

2021 ◽  
Vol 102 (11) ◽  
Author(s):  
Ralf G. Dietzgen ◽  
Andrew E. Firth ◽  
Dàohóng Jiāng ◽  
Sandra Junglen ◽  
Hideki Kondo ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Rna Polymerase ◽  
International Committee ◽  
Genome Organisation ◽  
Virus Taxonomy ◽  
Link Type ◽  
A Genome ◽  
The Family ◽  
Negative Sense

Nyamiviridae is a family of viruses in the order Mononegavirales, with unsegmented (except for members of the genus Tapwovirus), negative-sense RNA genomes of 10–13 kb. Nyamviruses have a genome organisation and content similar to that of other mononegaviruses. Nyamiviridae includes several genera that form monophyletic clades on phylogenetic analysis of the RNA polymerase. Nyamiviruses have been found associated with diverse invertebrates as well as land- and seabirds. Members of the genera Nyavirus and Socyvirus produce enveloped, spherical virions. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Nyamiviridae, which is available at ictv.global/report/nyamiviridae.

scholarly journals Satellite Subgenomic Particles Are Key Regulators of Adeno-Associated Virus Life Cycle

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1185
Author(s):  
Junping Zhang ◽  
Xiangping Yu ◽  
Ping Guo ◽  
Jenni Firrman ◽  
Derek Pouchnik ◽  
...  
Keyword(s):  
Viral Gene Expression ◽  
Viral Gene ◽  
Virus Population ◽  
Molecular Configuration ◽  
Adeno Associated Virus ◽  
Capsid Region ◽  
Double Stranded Rna ◽  
Defective Interfering Particles ◽  
Double Stranded Dna ◽  
Virus Life Cycle

Historically, adeno-associated virus (AAV)-defective interfering particles (DI) were known as abnormal virions arising from natural replication and encapsidation errors. Through single virion genome analysis, we revealed that a major category of DI particles contains a double-stranded DNA genome in a “snapback” configuration. The 5′- snapback genomes (SBGs) include the P5 promoters and partial rep gene sequences. The 3′-SBGs contains the capsid region. The molecular configuration of 5′-SBGs theoretically may allow double-stranded RNA transcription in their dimer configuration. Our studies demonstrated that 5-SBG regulated AAV rep expression and improved AAV packaging. In contrast, 3′-SBGs at its dimer configuration increased levels of cap protein. The generation and accumulation of 5′-SBGs and 3′-SBGs appears to be coordinated to balance the viral gene expression level. Therefore, the functions of 5′-SBGs and 3′-SBGs may help maximize the yield of AAV progenies. We postulate that AAV virus population behaved as a colony and utilizes its subgenomic particles to overcome the size limit of a viral genome and encodes additional essential functions.

Sign in / Sign up

Export Citation Format

Share Document