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Recent insights into the mechanism and consequences of TRIM5α retroviral restriction

Jaya Sastri1, Edward M Campbell

  • 1Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois 60153, USA.

AIDS Research and Human Retroviruses
|January 21, 2011
PubMed

Insights

The TRIM5 protein family restricts retroviral infections through species-specific binding to viral capsids. Genetic variations in TRIM5 influence immunodeficiency virus disease progression in humans and macaques.

Area of Science:

  • Virology
  • Immunology
  • Genetics

Background:

  • The TRIM5 protein family, including TRIM5α and TRIM-Cyp, acts as a cellular defense against retroviral infections.
  • TRIM5α exhibits species-specific restriction, with rhesus macaque TRIM5α (rhTRIM5α) inhibiting HIV-1 and human TRIM5α (huTRIM5α) inhibiting MLV.

Purpose of the Study:

  • To review the mechanisms of TRIM5-mediated retroviral restriction.
  • To discuss the impact of TRIM5 gene polymorphisms on immunodeficiency virus disease progression.

Main Methods:

  • Review of existing literature on TRIM5 function and retroviral restriction.
  • Analysis of proposed models for TRIM5-mediated capsid binding and disassembly.
  • Examination of studies linking TRIM5 polymorphisms to disease outcomes.

Main Results:

  • TRIM5 proteins restrict retroviruses by binding to viral capsid determinants.
  • TRIM5 self-association leads to capsid core compartmentalization and abortive disassembly.
  • Proteasome activity is implicated in the TRIM5 restriction mechanism.
  • Human and rhesus macaque TRIM5 polymorphisms correlate with varying immunodeficiency virus disease progression.

Conclusions:

  • TRIM5 proteins are key cellular factors in innate immunity against retroviruses.
  • Understanding TRIM5's species-specific restriction and its interaction with viral capsids is crucial.
  • TRIM5 polymorphisms represent a significant host factor influencing retroviral pathogenesis.

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