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Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production
08:32

Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production

Published on: March 2, 2014

DNA deamination mediates innate immunity to retroviral infection

Reuben S Harris1, Kate N Bishop, Ann M Sheehy

  • 1Medical Research Council Laboratory of Molecular Biology, Hills Road, CB2 2QH, Cambridge, United Kingdom. rharris@mrc-lmb.cam.ac.uk

Cell
|June 18, 2003
PubMed

Insights

CEM15/APOBEC3G is a DNA deaminase that fights retroviruses by altering viral DNA. Human immunodeficiency virus (HIV) Vif protein can overcome this innate immunity defense.

Area of Science:

  • Virology
  • Molecular Biology
  • Immunology

Background:

  • CEM15/APOBEC3G is crucial for defense against Vif-deficient HIV.
  • Retroviral infection mechanisms are complex and involve host-cell interactions.

Purpose of the Study:

  • To investigate the antiviral mechanism of CEM15/APOBEC3G.
  • To determine if CEM15/APOBEC3G acts as a DNA deaminase.
  • To explore the role of HIV Vif in overcoming CEM15/APOBEC3G restriction.

Main Methods:

  • Utilized a murine leukemia virus (MLV)-based system.
  • Analyzed the enzymatic activity of CEM15/APOBEC3G.
  • Assessed the impact of CEM15/APOBEC3G on retroviral cDNA.

Main Results:

  • CEM15/APOBEC3G is a DNA deaminase incorporated into virions.
  • It causes massive deamination of deoxycytidine to deoxyuridine in retroviral minus-strand cDNA.
  • HIV Vif confers protection against CEM15/APOBEC3G-mediated restriction.

Conclusions:

  • Targeted DNA deamination by CEM15/APOBEC3G is a key innate immunity strategy against retroviruses.
  • This deamination process likely contributes to viral sequence variation.
  • Understanding this interaction is vital for developing antiviral therapies.

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