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Immunodetection of Outer Membrane Proteins by Flow Cytometry of Isolated Mitochondria
11:53

Immunodetection of Outer Membrane Proteins by Flow Cytometry of Isolated Mitochondria

Published on: September 18, 2014

Theiler's virus L* protein is targeted to the mitochondrial outer membrane

Frédéric Sorgeloos1, Didier Vertommen, Mark H Rider

  • 1Université Catholique de Louvain, de Duve Institute, MIPA-VIRO 74-49, 74 Avenue Hippocrate, B-1200 Brussels, Belgium.

Journal of Virology
|January 14, 2011
PubMed

Insights

Theiler

Area of Science:

  • Virology
  • Molecular Biology
  • Neuroscience

Background:

  • Theiler's murine encephalomyelitis virus (TMEV) is a picornavirus.
  • The L* protein is encoded by an alternative reading frame.
  • L* protein is crucial for TMEV persistence in the central nervous system.

Purpose of the Study:

  • To investigate the subcellular localization and targeting mechanism of the TMEV L* protein.
  • To understand the role of L* protein in viral persistence.

Main Methods:

  • Cellular fractionation to separate cytosol and mitochondria.
  • Immunofluorescence microscopy to visualize L* protein localization.
  • Co-immunoprecipitation to study protein interactions.

Main Results:

  • The L* protein is found in both the cytosol and mitochondria of infected cells.
  • In mitochondria, L* is localized to the outer membrane, exposed to the cytosol.
  • Mitochondrial targeting of L* is independent of other viral factors and may involve Hsp70 chaperones.

Conclusions:

  • The TMEV L* protein exhibits unique mitochondrial localization.
  • Mitochondrial targeting of L* is likely mediated by a conformational signal and potentially Hsp70 chaperones.
  • Understanding L* localization provides insights into TMEV pathogenesis and persistence.

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