Modulation of HIV-like particle assemblyin vitroby inositol phosphates

Abstract
HIV-1 Gag protein assembles into 100- to 120-nm diameter particles in mammalian cells. Recombinant HIV-1 Gag protein assembles in a fully defined systemin vitrointo particles that are only 25–30 nm in diameter and that differ significantly in other respects from authentic particles. However, particles with the size and other properties of authentic virions were obtainedin vitroby addition of inositol phosphates or phosphatidylinsitol phosphates to the assembly system. Thus, the interactions between HIV-1 Gag protein molecules are altered by binding of inositol derivatives; this binding is apparently essential for normal HIV-1 particle assembly. This requirement is not seen in a deleted Gag protein lacking residues 16–99 within the matrix domain.