Identification of Nucleolar Factors During HIV-1 Replication Through Rev Immunoprecipitation and Mass Spectrometry

J Vis Exp. 2019 Jun 26:(148). doi: 10.3791/59329.

Abstract

The HIV-1 infectious cycle requires viral protein interactions with host factors to facilitate viral replication, packaging, and release. The infectious cycle further requires the formation of viral/host protein complexes with HIV-1 RNA to regulate the splicing and enable nucleocytoplasmic transport. The HIV-1 Rev protein accomplishes the nuclear export of HIV-1 mRNAs through multimerization with intronic cis-acting targets - the Rev response element (RRE). A nucleolar localization signal (NoLS) exists within the COOH-terminus of the Rev arginine-rich motif (ARM), allowing the accumulation of Rev/RRE complexes in the nucleolus. Nucleolar factors are speculated to support the HIV-1 infectious cycle through various other functions in addition to mediating mRNA-independent nuclear export and splicing. We describe an immunoprecipitation method of wild-type (WT) Rev in comparison to Rev nucleolar mutations (deletion and single-point Rev-NoLS mutations) in the presence of HIV-1 replication for mass spectrometry. Nucleolar factors implicated in the nucleocytoplasmic transport (nucleophosmin B23 and nucleolin C23), as well as cellular splicing factors, lose interaction with Rev in the presence of Rev-NoLS mutations. Various other nucleolar factors, such as snoRNA C/D box 58, are identified to lose interaction with Rev mutations, yet their function in the HIV-1 replication cycle remain unknown. The results presented here demonstrate the use of this approach for the identification of viral/host nucleolar factors that maintain the HIV-1 infectious cycle. The concepts used in this approach are applicable to other viral and disease models requiring the characterization of understudied pathways.

Publication types

  • Research Support, N.I.H., Extramural
  • Video-Audio Media

MeSH terms

  • Cell Nucleolus / metabolism*
  • HIV-1 / genetics
  • HIV-1 / physiology*
  • HeLa Cells
  • Humans
  • Immunoprecipitation*
  • Mass Spectrometry*
  • Mutation / genetics
  • Protein Sorting Signals / genetics
  • RNA, Viral / genetics
  • Virus Replication / physiology*
  • rev Gene Products, Human Immunodeficiency Virus / metabolism*

Substances

  • Protein Sorting Signals
  • RNA, Viral
  • rev Gene Products, Human Immunodeficiency Virus
  • rev protein, Human Immunodeficiency Virus-1