Related Experiment Video
Updated: Jun 20, 2026
18:10
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Replication mode and landscape topology differentially affect RNA virus mutational load and robustness
Josep Sardanyés1, Ricard V Solé, Santiago F Elena
1Complex Systems Lab (ICREA-UPF), Barcelona Biomedical Research Park, 08003 Barcelona, Spain. josep.sardanes@upf.edu
Journal of Virology
|September 25, 2009
Summary
RNA viruses can enhance robustness against deleterious mutations by using the stamping machine replication model over geometric growth. This benefit
Area of Science:
- Virology
- Evolutionary Biology
- Mathematical Modeling
Background:
- Viral genome replication involves synthesizing complementary strands, with different models (geometric vs. stamping machine) affecting mutant genome distribution.
- Understanding replication mechanisms is crucial for predicting viral evolution and robustness against mutations.
Purpose of the Study:
- To develop mathematical and bit string models to differentiate between geometric and stamping machine replication mechanisms.
- To analyze the impact of these replication models on mutant genome abundance, distribution, and critical mutation rates.
Main Methods:
- Development of mathematical and bit string models to simulate viral replication dynamics.
- Analysis of critical mutation rates, mutation accumulation, and population dynamics under different replication schemes.
- Investigation of the influence of fitness landscape topology, epistasis, and mutation effect size.
Main Results:
- The critical mutation rate increases when switching from geometric to stamping machine replication, enhancing robustness.
- Mild mutations accumulate more in geometric replication, while large-effect mutations do not accumulate significantly in either model.
- Geometric growth leads to population collapse at high mutation rates, whereas stamping machine replication maintains master genomes.
Conclusions:
- RNA viruses can improve robustness against deleterious mutations by employing the stamping machine replication strategy.
- The effectiveness of the stamping machine model depends on the fitness landscape's epistasis, particularly synergistic epistasis.
- Replication mechanisms significantly influence viral population dynamics and evolutionary trajectories under mutational pressure.
Related Concept Videos
00:36Viral Mutations
A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material for adaptive...
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...
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...
01:18Mutations in Microorganisms
Mutations are heritable changes in an organism’s genome involving alterations in the base sequence of DNA or RNA. These changes can influence cellular processes and phenotypic traits, potentially transforming the unaltered wild type into a mutant form. Such changes, termed forward mutations, are pivotal in shaping the genetic diversity of organisms.RNA viruses exhibit the highest mutation rates due to the absence of robust proofreading mechanisms during genome replication. In contrast,...
01:20Mismatch Repair
Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
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...