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A circadian model for viral persistence

Farhad F Shadan1

  • 1The Scripps Research Institute and Scripps Clinic, 10666 N. Torrey Pines Road, 403C, La Jolla, CA 92037, USA. ffshadan@yahoo.com

Medical Hypotheses
|October 13, 2006
PubMed

Insights

Persistent viruses may use the body's internal clock to regulate DNA replication, potentially causing genome instability and increasing cancer risk. This links viral infections to circadian rhythms and DNA repair.

Area of Science:

  • Virology
  • Molecular Biology
  • Chronobiology

Background:

  • Persistently infecting DNA viruses rely on host cell DNA synthesis.
  • Mutagenic stress inhibits both cellular and viral DNA replication.

Purpose of the Study:

  • To investigate the hypothesis that diurnal regulation of viral DNA replication occurs via cell cycle checkpoints and DNA repair.
  • To explore the evolutionary origins and molecular links between viral DNA replication and the circadian clock.

Main Methods:

  • Tracing conserved mechanisms in prokaryotic and eukaryotic viruses.
  • Analyzing interactions between viral promoters, proteins, transcription factors, and the circadian clock.
  • Modeling the desynchrony between viral oncogene expression and tumor suppressor/DNA repair genes.

Main Results:

  • UV light exposure inhibits viral DNA replication and the cell cycle, suggesting a role in circadian-gated replication evolution.
  • Viral DNA replication is closely linked to the circadian clock through various molecular interactions.
  • Phase-shifting of viral oncogene expression can lead to desynchrony with DNA repair mechanisms.

Conclusions:

  • Diurnal regulation of viral DNA replication may protect against genotoxic stress.
  • Temporal vulnerability to genotoxic stress can create a "mutator phenotype" and genome instability.
  • The proposed model has implications for understanding viral pathogenesis and developing therapeutics.

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