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Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites
09:31

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Published on: March 22, 2016

Human immunodeficiency virus type 1 DNA nuclear import and integration are mitosis independent in cycling cells

Richard A Katz1, James G Greger, Pamela Boimel

  • 1Institute for Cancer Research, Fox Chase Cancer Center, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19111, USA. R_Katz@fccc.edu

Journal of Virology
|December 4, 2003
PubMed

Insights

Human immunodeficiency virus type 1 (HIV-1) DNA enters the nucleus and integrates into host DNA before the cell divides. This nuclear entry is efficient even without cell division, challenging previous assumptions about HIV-1 replication.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • Human immunodeficiency virus type 1 (HIV-1) replication requires nuclear entry of the viral preintegration complex.
  • The precise mechanisms and timing of nuclear entry for HIV-1 DNA in actively dividing cells remain unclear.

Purpose of the Study:

  • To investigate the pathway and timing of nuclear entry for HIV-1 DNA in cycling cells.
  • To determine if nuclear entry is dependent on mitotic nuclear disassembly.

Main Methods:

  • Infection of cycling cells prior to S phase.
  • Analysis of viral DNA integration and stable inheritance in daughter cells.

Main Results:

  • HIV-1 DNA can be integrated into the host genome before the host DNA replication fork passes the integration site.
  • Stable inheritance of integrated viral DNA is observed in both daughter cells following infection before S phase.

Conclusions:

  • Efficient nuclear entry of HIV-1 DNA can occur independently of mitotic nuclear disassembly in cycling cells.
  • This finding provides new insights into the early stages of HIV-1 replication in dividing cells.

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