Nef Binds p6* in GagPol during Replication of Human Immunodeficiency Virus Type 1

AUTOR(ES)

Costa, Luciana J.

FONTE

American Society for Microbiology

RESUMO

The atypical Nef protein (NefF12) from human immunodeficiency virus type 1 strain F12 (HIV-1F12) interferes with virion production and infectivity via a mysterious mechanism. The correlation of these effects with the unusual perinuclear subcellular localization of NefF12 suggested that the wild-type Nef protein could bind to assembly intermediates in late stages of viral replication. To test this hypothesis, Nef from HIV-1NL4-3 was fused to an endoplasmic reticulum (ER) retention signal (NefKKXX). This mutant NefKKXX protein recapitulated fully the effects of NefF12 on Gag processing and virion production, either alone or as a CD8 fusion protein. Importantly, the mutant NefKKXX protein also localized to the intermediate compartment, between the ER and the trans-Golgi network. Furthermore, Nef bound the GagPol polyprotein in vitro and in vivo. This binding mapped to the C-terminal flexible loop in Nef and the transframe p6* protein in GagPol. The significance of this interaction was demonstrated by a genetic assay in which the release of a mutant HIV-1 provirus lacking the PTAP motif in the late domain that no longer binds Tsg101 was rescued by a Nef.Tsg101 chimera. Importantly, this rescue as well as incorporation of Nef into HIV-1 virions correlated with the ability of Nef to interact with GagPol. Our data demonstrate that the retention of Nef in the intermediate compartment interferes with viral replication and suggest a new role for Nef in the production of HIV-1.

Documentos Relacionados

• Incorporation of Pol into Human Immunodeficiency Virus Type 1 Gag Virus-Like Particles Occurs Independently of the Upstream Gag Domain in Gag-Pol
• Functional Human Immunodeficiency Virus Type 1 (HIV-1) Gag-Pol or HIV-1 Gag-Pol and Env Expressed from a Single Rhabdovirus-Based Vaccine Vector Genome
• Identification of a Key Target Sequence To Block Human Immunodeficiency Virus Type 1 Replication within the gag-pol Transframe Domain
• Novel Gag-Pol Frameshift Site in Human Immunodeficiency Virus Type 1 Variants Resistant to Protease Inhibitors
• Mutations of the Human Immunodeficiency Virus Type 1 p6Gag Domain Result in Reduced Retention of Pol Proteins during Virus Assembly