A highly conserved residue in the C-terminal helix of HIV-1 matrix is required for envelope incorporation into virus particles

Laura Brandano, Mario Stevenson

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

The incorporation of viral envelope (Env) glycoproteins into nascent particles is an essential step in the production of infectious human immunodeficiency virus type 1 (HIV-1). This process has been shown to require interactions between Env and the matrix (MA) domain of the Gag polyprotein. Previous studies indicate that several residues in the N-terminal region of MA are required for Env incorporation. However, the precise mechanism by which Env proteins are acquired during virus assembly has yet to be fully defined. Here, we examine whether a highly conserved glutamate at position 99 in the C-terminal helix is required for MA function and HIV-1 replication. We analyze a panel of mutant viruses that contain different amino acid substitutions at this position using viral infectivity studies, virus-cell fusion assays, and immunoblotting. We find that E99V mutant viruses are defective for fusion with cell membranes and thus are noninfectious. We show that E99V mutant particles of HIV-1 strains LAI and NL4.3 lack wild-type levels of Env proteins. We identify a compensatory substitution in MA residue 84 and show that it can reverse the E99V-associated defects. Taken together, these results indicate that the C-terminal hydrophobic pocket of MA, which encompasses both residues 84 and 99, has a previously unsuspected and key role in HIV-1 Env incorporation.

Original languageEnglish
Pages (from-to)2347-2359
Number of pages13
JournalJournal of Virology
Volume86
Issue number4
DOIs
StatePublished - Feb 1 2012

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Human immunodeficiency virus 1
virion
Virion
HIV-1
viruses
mutants
Viruses
Defective Viruses
gag Gene Products
Virus Assembly
cell fusion
Cell Fusion
amino acid substitution
Amino Acid Substitution
Virus Replication
immunoblotting
Immunoblotting
glutamates
cell membranes
glycoproteins

ASJC Scopus subject areas

  • Immunology
  • Virology

Cite this

A highly conserved residue in the C-terminal helix of HIV-1 matrix is required for envelope incorporation into virus particles. / Brandano, Laura; Stevenson, Mario.

In: Journal of Virology, Vol. 86, No. 4, 01.02.2012, p. 2347-2359.

Research output: Contribution to journalArticle

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