Mutational analysis of the HIV-1 auxiliary protein Vif identifies independent domains important for the physical and functional interaction with HIV-1 reverse transcriptase

Nucleic Acids Res. 2009 Jun;37(11):3660-9. doi: 10.1093/nar/gkp226. Epub 2009 Apr 15.

Abstract

The HIV-1 accessory protein Vif plays a dual role: it counteracts the natural restriction factors APOBEC3G and 3F and ensures efficient retrotranscription of the HIV-1 RNA genome. We have previously shown that Vif can act as an auxiliary factor for HIV-1 reverse transcriptase (RT), increasing its rate of association to RNA or DNA templates. Here, by using seven different Vif mutants, we provide in vitro evidences that Vif stimulates HIV-1 RT through direct protein-protein interaction, which is mediated by its C-terminal domain. Physical interaction appears to require the proline-rich region comprised between amino acid (aa) 161 and 164 of Vif, whereas the RT stimulatory activity requires, in addition, the extreme C-terminal region (aa 169-192) of the Vif protein. Neither the RNA interaction domain, nor the Zn(++)-binding domain of Vif are required for its interaction with the viral RT. Pseudotyped HIV-1 lentiviral vectors bearing Vif mutants deleted in the RNA- or RT-binding domains show defects in retrotranscription/integration processes in both permissive and nonpermissive cells. Our results broaden our knowledge on how three important functions of Vif (RNA binding, RT binding and stimulation and Zn(++) binding), are coordinated by different domains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • HIV Reverse Transcriptase / metabolism*
  • Humans
  • Mutation
  • Protein Binding
  • Protein Interaction Domains and Motifs
  • RNA / metabolism
  • Reverse Transcription
  • Virus Integration
  • Zinc Fingers
  • vif Gene Products, Human Immunodeficiency Virus / chemistry*
  • vif Gene Products, Human Immunodeficiency Virus / genetics
  • vif Gene Products, Human Immunodeficiency Virus / metabolism

Substances

  • vif Gene Products, Human Immunodeficiency Virus
  • vif protein, Human immunodeficiency virus 1
  • RNA
  • reverse transcriptase, Human immunodeficiency virus 1
  • HIV Reverse Transcriptase