Related Experiment Video
Updated: May 12, 2026
10:22
Isolation of Viral Replication Compartment-enriched Sub-nuclear Fractions from Adenovirus-infected Normal Human Cells
Published on: November 12, 2015
Analysis of classical swine fever virus RNA replication determinants using replicons
Peter Christian Risager1, Ulrik Fahnøe1, Maria Gullberg1
1National Veterinary Institute, Technical University of Denmark, Lindholm, Kalvehave 4771, Denmark.
The Journal of General Virology
|April 13, 2013
Summary
Researchers developed self-replicating RNA (replicon) systems from classical swine fever virus (CSFV). These systems allow studying CSFV genome replication without needing infectious virus, identifying key regions for replication.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- Classical swine fever virus (CSFV) poses a significant threat to swine populations globally.
- Understanding CSFV genome replication is crucial for developing effective control strategies.
- Previous studies on CSFV replication were limited by the need for infectious virus.
Purpose of the Study:
- To create and characterize self-replicating RNA (replicon) systems derived from CSFV.
- To identify specific CSFV genomic regions essential for RNA replication.
- To establish a system for studying CSFV replication independent of viral infectivity.
Main Methods:
- Production of CSFV replicons from modified bacterial artificial chromosomes.
- In vitro transcription and electroporation of replicon RNAs into cells.
- Monitoring replication via reporter gene expression (luciferase) and detection of viral proteins (CSFV NS3).
- Construction and analysis of chimeric replicons with sequence variations from different CSFV strains.
Main Results:
- Inclusion of the CSFV E2 coding region enhanced replicon replication efficiency.
- Substitution of NS2/NS3 coding regions from different strains blocked replication.
- Replacing the Paderborn NS5B sequence with the Koslov strain's RNA polymerase enhanced reporter protein expression.
- Replacing Paderborn NS5B with the Riems strain's NS5B significantly impaired replication.
Conclusions:
- CSFV replicons provide a valuable tool for dissecting genome replication mechanisms.
- Specific regions, particularly NS5B, play critical roles in CSFV RNA replication efficiency.
- This system facilitates the study of CSFV genome replication without the need for infectious virus, aiding in the development of antiviral strategies.
Related Concept Videos
01:29Viruses with RNA Genomes
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...
01:26Size and Structure of Viral Genomes
Viral genomes exhibit remarkable diversity in size, structure, and composition, influencing their replication strategies and interactions with host cells. These genomes consist of either DNA or RNA and may be linear or circular. Additionally, they can be single-stranded or double-stranded, with each configuration affecting how the virus propagates within a host. RNA viruses, for instance, generally have smaller genomes than DNA viruses, a factor that contributes to their high mutation rates and...
02:28Leaky Scanning
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
01:10Retrovirus Life Cycles
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 retrovirus to...
01:29Subviral Agents
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...
01:30Inhibitors of Viral Protein Synthesis
Protein synthesis is indispensable for viral replication, as viruses lack the cellular machinery required for this process and must hijack the host's translational apparatus. In response, host cells deploy a critical innate immune defense involving interferons, specialized cytokines that play a central role in inhibiting viral propagation.Upon viral detection, infected cells release interferons that bind to receptors on adjacent uninfected cells, activating the JAK-STAT signaling pathway and...