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Human immunodeficiency virus type 1 Vpu protein is an oligomeric type I integral membrane protein

F Maldarelli1, M Y Chen, R L Willey

  • 1Laboratory of Molecular Microbiology, National Institutes of Health, Bethesda, Maryland 20892.

Journal of Virology
|August 1, 1993
PubMed

Insights

The human immunodeficiency virus type 1 Vpu protein is a type I integral membrane protein. It can also form complexes with other Vpu proteins, indicating its ability to multimerize.

Area of Science:

  • Virology
  • Molecular Biology
  • Cell Biology

Background:

  • Human immunodeficiency virus type 1 (HIV-1) Vpu protein enhances virion production.
  • Vpu induces rapid degradation of CD4, the cellular receptor for HIV.
  • Understanding Vpu's structure and function is crucial for HIV-1 research.

Purpose of the Study:

  • To investigate the topology of membrane-inserted Vpu.
  • To determine if Vpu forms complexes with other proteins.
  • To elucidate the oligomeric state of Vpu within the cell.

Main Methods:

  • In vitro synthesis of Vpu and cotranslational insertion into canine microsomal membranes.
  • Proteolytic digestion and immunoprecipitation to determine Vpu topology.
  • Chemical cross-linking, one- and two-dimensional electrophoresis to identify Vpu complexes.

Main Results:

  • Vpu is a type I integral membrane protein with its hydrophilic domain exposed on the cytoplasmic face.
  • High-molecular-weight complexes containing Vpu were identified.
  • These complexes were found to be homo-oligomers of Vpu.

Conclusions:

  • Vpu is a type I integral membrane protein.
  • Vpu possesses the capability to multimerize, forming homo-oligomers.
  • These findings contribute to understanding Vpu's role in HIV-1 replication and pathogenesis.

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