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Identification of Nucleolar Factors During HIV-1 Replication Through Rev Immunoprecipitation and Mass Spectrometry
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Retroviral mRNA nuclear export elements regulate protein function and virion assembly

Chad M Swanson1, Bridget A Puffer, K Muneer Ahmad

  • 1Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.

The EMBO Journal
|June 18, 2004
PubMed

Insights

Murine cells cannot assemble HIV. Researchers found that changing the HIV gag-pol mRNA export pathway restored Gag trafficking and HIV assembly in rodent cells, linking RNA export to capsid assembly.

Area of Science:

  • Virology
  • Molecular Biology
  • Cell Biology

Background:

  • Rodent cells exhibit a defect in normal human immunodeficiency virus (HIV) particle assembly.
  • The underlying causes for this defect are not fully understood, particularly regarding the role of mRNA-associated events in regulating protein activity.

Purpose of the Study:

  • To investigate the hypothesis that nuclear mRNA-associated events regulate cytoplasmic protein activity in the context of HIV assembly.
  • To identify specific mechanisms contributing to the inability of rodent cells to support HIV assembly.

Main Methods:

  • The study manipulated the RNA nuclear export element of HIV gag-pol mRNA.
  • The Rev response element (RRE) was replaced with the constitutive transport element (CTE).
  • Gag protein trafficking and HIV assembly efficiency were assessed in murine cells.

Main Results:

  • Altering the HIV gag-pol mRNA export pathway from RRE to CTE restored Gag protein trafficking to cellular membranes in murine cells.
  • Efficient HIV particle assembly was restored in rodent cells following this modification.
  • These findings demonstrate a link between RNA export and capsid assembly.

Conclusions:

  • The HIV life cycle phases of RNA export and capsid assembly are functionally linked, not distinct.
  • The history of an mRNA, including its export pathway, can influence the function and fate of its encoded protein.
  • This provides a novel perspective on regulating viral assembly and protein function.

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