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Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
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G-quadruplexes in pathogens: a common route to virulence control?
Lynne M Harris1, Catherine J Merrick1
1Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Keele, Staffordshire, United Kingdom.
Plos Pathogens
|February 6, 2015
Summary
G-quadruplexes (G4s) are DNA structures that pathogens use to evade the immune system. These structures play roles in microbial virulence, aiding chronic infections by affecting DNA and RNA dynamics.
Area of Science:
- Molecular Biology
- Genetics
- Microbiology
Background:
- DNA forms secondary structures beyond the double helix, including G-quadruplexes (G4s), which are stable, four-stranded formations of guanine bases.
- G4s are increasingly recognized for their in vivo and in vitro roles, influencing DNA replication and transcription, particularly at G-rich telomeres.
Purpose of the Study:
- To review the emerging evidence for G-quadruplex (G4) structures in the virulence mechanisms of human microbial pathogens.
- To explore how G4s facilitate immune evasion across diverse pathogens, including bacteria, protozoa, and viruses.
Main Methods:
- Literature review of recent reports on G4 structures in microbial pathogenesis.
- Analysis of G4 roles in immune evasion strategies such as antigenic variation and viral gene silencing.
Main Results:
- G4 structures are implicated in the virulence of various human pathogens, spanning bacteria, protozoa, and viruses.
- These G4 motifs contribute to immune evasion through mechanisms like antigenic variation in bacteria/protozoa and silencing of human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV).
Conclusions:
- G-quadruplexes represent a common strategy employed by disparate pathogens to manipulate DNA/RNA dynamics for virulence.
- Understanding G4 biology in pathogens offers insights into maintaining chronic infections and developing novel therapeutic strategies.
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