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HIV-1 Gag protein associates with F-actin present in microfilaments

O Rey1, J Canon, P Krogstad

  • 1Department of Pediatrics, School of Medicine, University of California at Los Angeles 90095, USA. <orey@pediatrics.medsch.ucla.edu>

Virology
|June 15, 1996
PubMed

Insights

The unprocessed Gag polyprotein of human immunodeficiency virus type 1 (HIV-1) interacts with polymerized actin (F-actin). This binding to the cellular cytoskeleton may play a role in HIV-1 assembly and budding.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • The cellular cytoskeleton is increasingly recognized for its potential role in retroviral replication.
  • Specific interactions between viral proteins and host cell components are crucial for viral assembly and release.

Purpose of the Study:

  • To investigate the interaction between the human immunodeficiency virus type 1 (HIV-1) Gag polyprotein and the cellular cytoskeleton.
  • To determine if Gag polyprotein associates with polymerized actin (F-actin).

Main Methods:

  • Fractionation studies of HIV-1-infected CEM cells.
  • In vivo and in vitro analyses of Gag polyprotein-cytoskeleton interactions.

Main Results:

  • The majority of unprocessed HIV-1 Gag polyprotein cofractionated with the cellular cytoskeleton in infected cells.
  • Gag polyprotein demonstrated the ability to associate with polymerized actin (F-actin).

Conclusions:

  • The unprocessed Gag polyprotein of HIV-1 interacts with polymerized actin.
  • This interaction with F-actin is a potential mechanism involved in the assembly and budding of HIV-1 particles.

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