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Single amino acid changes in the human immunodeficiency virus type 1 matrix protein block virus particle production

E O Freed1, J M Orenstein, A J Buckler-White

  • 1Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892.

Journal of Virology
|August 1, 1994
PubMed

Insights

Researchers identified key regions in the human immunodeficiency virus type 1 matrix protein essential for virus particle assembly. Mutations in these domains significantly impair virus production and alter assembly sites.

Area of Science:

  • Virology
  • Molecular Biology
  • Structural Biology

Background:

  • The matrix protein (MA) of human immunodeficiency virus type 1 (HIV-1) is crucial for viral structure and function.
  • MA is derived from the Gag precursor and plays a role in the virus life cycle, including particle assembly.

Purpose of the Study:

  • To pinpoint specific domains and amino acid residues within the HIV-1 MA protein involved in virus particle assembly.
  • To understand how mutations in MA affect viral production and infectivity.

Main Methods:

  • Introduction of 35 amino acid substitution mutations into the HIV-1 MA protein.
  • Analysis of viral particle formation using reverse transcriptase assays and radioimmunoprecipitation.
  • Assessment of viral assembly and morphology via transmission electron microscopy.

Main Results:

  • Identified critical domains within the MA protein where single amino acid substitutions severely reduce virus particle production.
  • Specific domains identified include the N-terminal six residues, the region between amino acids 55-59, and the region between amino acids 84-95.
  • Mutations between amino acids 84-88 of MA caused a significant redirection of virus particle formation to cytoplasmic vacuoles.

Conclusions:

  • Specific regions of the HIV-1 matrix protein are essential for efficient virus particle production.
  • Alterations in these MA domains can disrupt normal viral assembly pathways and localization.
  • Understanding these MA domains provides insights into HIV-1 replication and potential therapeutic targets.

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