Interactions in vivo between the Vif protein of HIV-1 and the precursor (Pr55(GAG)) of the virion nucleocapsid proteins.
The abnormality of viral core structure seen in vif-defective HIV-1 grown in PBMCs has suggested a role for Vif in viral morphogenesis. Using an in vivo mammalian two-hybrid assay, the interaction between Vif and the precursor (Pr55(GAG)) of the virion nucleocapsid proteins has been analysed. This revealed the amino-terminal (aa 1-22) and central (aa 70-100) regions of Vif to be essential for its interaction with Pr55(GAG), but deletion of the carboxy-terminal (aa 158-192) region of the protein had only a minor effect on its interaction. Initial deletion studies carried out on Pr55(GAG) showed that a 35-amino-acid region of the protein bridging the MA(p17)-CA(p24) junction was essential for its ability to interact with Vif. Site-directed mutagenesis of a conserved tryptophan (Trp(21)) near the amino terminus of Vif showed it to be important for the interaction with Pr55(GAG). By contrast, mutagenesis of the highly conserved YLAL residues forming part of the BC-box motif, shown to be important in Vif promoting degradation of APOBEC3G/3F, had little or no effect on the Vif-Pr55(GAG) interaction.
Syed
Farhatullah
F
Department of Biological Sciences, University of Warwick, Coventry, CV4 7AL, UK.
McCrae
Malcolm A
MA
D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D017353:Gene Deletion; D015967:Gene Expression Regulation, Viral / Q000502:physiology*; D005978:Glutathione; D015497:HIV-1 / Q000378:metabolism*; D011498:Protein Precursors / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D014771:Virion / Q000502:physiology; D054320:vif Gene Products, Human Immunodeficiency Virus / Q000378:metabolism*
D011498:Protein Precursors; C059767:p55 gag precursor protein, Human immunodeficiency virus 1; D054320:vif Gene Products, Human Immunodeficiency Virus; C514847:vif protein, Human immunodeficiency virus 1; D005978:Glutathione