Related Experiment Video
Updated: Oct 14, 2025
10:03
Generation of Recombinant Arenavirus for Vaccine Development in FDA-Approved Vero Cells
Published on: August 1, 2013
17.2K
[Animal circoviruses and associated diseases].
B Grasland1, L Bigarré1, P Blanchard1
1Unité de génétique virale et biosécurité, Agence française de sécurité sanitaire des aliments (Afssa), BP53, 22440 Ploufragan.
Virologie (Montrouge, France)
|November 4, 2021
Summary
Animal circoviruses, affecting swine and birds, possess a single-stranded circular genome crucial for replication. Most circoviruses cause immunosuppressive diseases, with no current medical prophylaxis available.
Area of Science:
- Virology
- Molecular Biology
Context:
- Circoviruses are a genus within the Circoviridae family, primarily infecting swine and birds.
- These viruses feature a single-stranded circular genome of approximately 2000 nucleotides.
Purpose:
- To describe the genetic and structural characteristics of animal circoviruses.
- To highlight the pathogenic associations and clinical manifestations of circovirus infections.
Summary:
- Circovirus genomes contain a replication origin with a nonanucleotide sequence and inverted repeats, forming a stem-loop structure.
- Two major open reading frames (ORFs) encode the replication-associated protein (Rep) and capsid protein (Cap).
- Most circoviruses, excluding porcine circovirus type 1, are linked to immunosuppressive or immunodepressive diseases, characterized by histopathological lesions like cytoplasmic inclusions and lymphocyte depletion.
Impact:
- Understanding circovirus structure and replication is vital for disease management.
- The lack of medical prophylaxis underscores the need for further research into prevention and treatment strategies for circovirus infections in animals.
Related Concept Videos
00:57Viral Recombination
24.0K
Cells are sometimes infected by more than one virus at once. When two viruses disassemble to expose their genomes for replication in the same cell, similar regions of their genomes can pair together and exchange sequences in a process called recombination. Alternatively, viruses with segmented genomes can swap segments in a process called reassortment.
24.0K
01:29Subviral Agents
203
Subviral agents are infectious entities that resemble viruses but lack one or more viral components, such as a capsid or essential replication machinery. These agents include viroids, prions, and satellites, each possessing distinct structural and functional characteristics that influence their mode of infection and replication.Viroids are the simplest subviral agents, consisting of circular, single-stranded RNA molecules without a protein coat. They exclusively infect plants, relying entirely...
203
01:03Rous Sarcoma Virus (RSV) and Cancer
5.6K
Rous Sarcoma virus or RSV was discovered by F. Peyton Rous in the year 1911 as a filterable transmissible agent that could cause tumors in chickens. He won a Nobel Prize for this discovery in 1966. His experiments clearly demonstrated that some cancers could be caused by infectious agents and led to the discovery of many more cancer-causing viruses in animals as well as humans.
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
5.6K
01:51Mechanisms of Retrovirus-induced Cancers
5.4K
Retroviruses are RNA viruses that have been shown to cause cancers in diverse species, including chickens, mice, cats, and monkeys. The RNA genomes of these viruses are first reverse-transcribed into single and then double-stranded DNA (dsDNA) copies. This dsDNA called proviral DNA then integrates into the host genome. Subsequently, the host cell transcribes the proviral DNA in concert with the chromosomal DNA. This leads to the production of viral RNA and proteins that assemble at the host...
5.4K
01:10Retrovirus Life Cycles
47.6K
Retroviruses have a single-stranded RNA genome that undergoes a special form of replication. Once the retrovirus has entered the host cell, an enzyme called reverse transcriptase synthesizes double-stranded DNA from the retroviral RNA genome. This DNA copy of the genome is then integrated into the host’s genome inside the nucleus via an enzyme called integrase. Consequently, the retroviral genome is transcribed into RNA whenever the host’s genome is transcribed, allowing the...
47.6K
01:29Viruses with RNA Genomes
226
RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...
226