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A role for DNA-PK in retroviral DNA integration

R Daniel1, R A Katz, A M Skalka

  • 1Institute for Cancer Research, Fox Chase Cancer Center, 7701 Burholme Avenue, Philadelphia, PA 19111, USA.

Science (New York, N.Y.)
|April 24, 1999
PubMed

Insights

Host cell DNA-PK aids retroviral DNA integration. DNA-PK-deficient cells show reduced integration and apoptosis, indicating DNA-PK is crucial for completing integration and preventing cell death.

Area of Science:

  • Molecular biology
  • Virology
  • Cell biology

Background:

  • Retroviral DNA integration is essential for viral replication, catalyzed by viral integrase.
  • Host cell factors can influence viral processes, but their roles in integration are not fully understood.

Purpose of the Study:

  • To investigate the role of host cell proteins in retroviral DNA integration.
  • To determine if DNA-dependent protein kinase (DNA-PK) participates in retroviral integration.

Main Methods:

  • Infection of DNA-PK-deficient murine scid cells with different retroviruses.
  • Assessment of retroviral DNA integration efficiency.
  • Observation of cell viability and apoptosis following infection.

Main Results:

  • DNA-PK-deficient scid cells exhibited a significant reduction in retroviral DNA integration.
  • Infection led to apoptosis in scid cells, but only with integrase-proficient viruses.
  • Integrase-defective viruses did not induce cell death, suggesting abortive integration triggers apoptosis.

Conclusions:

  • Host cell DNA-PK is a critical factor in retroviral DNA integration.
  • The host cell recognizes early retroviral integration events as DNA damage.
  • Completion of retroviral integration requires the DNA-PK-mediated DNA repair pathway.

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