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In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
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Ubiquitin is part of the retrovirus budding machinery

A Patnaik1, V Chau, J W Wills

  • 1Department of Microbiology and Immunology and Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, 500 University Drive, P.O. Box 850, Hershey, PA 17033, USA.

Proceedings of the National Academy of Sciences of the United States of America
|November 23, 2000
PubMed

Insights

Ubiquitin, a cellular protein, is crucial for retrovirus release. Reduced ubiquitin levels hinder Rous sarcoma virus budding, indicating its role in viral particle machinery.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • Retroviruses contain significant amounts of ubiquitin.
  • The functional role of ubiquitin in retroviral replication has been unclear.

Purpose of the Study:

  • To investigate the significance of ubiquitin in retroviral release.
  • To determine if ubiquitin is involved in the viral budding process.

Main Methods:

  • Utilized drugs to reduce cellular free ubiquitin levels.
  • Overexpressed ubiquitin and fused it to the Gag protein.
  • Employed electron microscopy to visualize viral budding.

Main Results:

  • Drugs reducing free ubiquitin significantly inhibited Rous sarcoma virus release.
  • Ubiquitin overexpression and Gag fusion suppressed the budding defect.
  • Electron microscopy showed impaired particle separation from the plasma membrane.

Conclusions:

  • Ubiquitin plays a critical role in the retroviral budding machinery.
  • Ubiquitin is essential for the efficient release of mature retroviral particles.

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