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. 1996 Apr 2;93(7):3099–3104. doi: 10.1073/pnas.93.7.3099

Crystal structures of the trimeric human immunodeficiency virus type 1 matrix protein: implications for membrane association and assembly.

C P Hill 1, D Worthylake 1, D P Bancroft 1, A M Christensen 1, W I Sundquist 1
PMCID: PMC39768  PMID: 8610175

Abstract

The human immunodeficiency virus type 1 (HIV-1) matrix protein forms a structural shell associated with the inner viral membrane and performs other essential functions throughout the viral life cycle. The crystal structure of the HIV-1 matrix protein, determined at 2.3 angstrom resolution, reveals that individual matrix molecules are composed of five major helices capped by a three-stranded mixed beta-sheet. Unexpectedly, the protein assembles into a trimer in three different crystal lattices, burying 1880 angstrom2 of accessible surface area at the trimer interfaces. Trimerization appears to create a large, bipartite membrane binding surface in which exposed basic residues could cooperate with the N-terminal myristoyl groups to anchor the protein on the acidic inner membrane of the virus.

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Selected References

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