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Title: Degradation of the encephalomyocarditis virus and hepatitis A virus 3C proteases by the ubiquitin/26S proteasome system in vivo

Abstract

We have isolated stably transfected mouse embryonic fibroblast cell lines that inducibly express either the mature encephalomyocarditis virus (EMCV) or hepatitis A virus (HAV) 3C protease and have used these cells to demonstrate that both proteins are subject to degradation in vivo by the ubiquitin/26S proteasome system. The detection of 3C protease expression in these cells requires inducing conditions and the presence of one of several proteasome inhibitors. Both 3C proteases are incorporated into conjugates with ubiquitin in vivo. HAV 3C protease expression has deleterious effects on cell viability, as determined by observation and counting of cells cultured in the absence or presence of inducing conditions. The EMCV 3C protease was found to be preferentially localized to the nucleus of induced cells, while the HAV 3C protease remains in the cytoplasm. The absence of polyubiquitinated EMCV 3C protease conjugates in nuclear fraction preparations suggests that localization to the nucleus can protect this protein from ubiquitination.

Authors:
 [1];  [2];  [2];  [2];  [3]
  1. Department of Chemistry, Bates College, Lewiston, ME 04240 (United States)
  2. Biological Chemistry Program, Bates College, Lewiston, ME 04240 (United States)
  3. Department of Chemistry, Bates College, Lewiston, ME 04240 (United States) and Biological Chemistry Program, Bates College, Lewiston, ME 04240 (United States). E-mail: tlawson@bates.edu
Publication Date:
OSTI Identifier:
20977011
Resource Type:
Journal Article
Resource Relation:
Journal Name: Virology; Journal Volume: 360; Journal Issue: 2; Other Information: DOI: 10.1016/j.virol.2006.10.043; PII: S0042-6822(06)00799-9; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CYTOPLASM; FIBROBLASTS; HEPATITIS; IN VIVO; MICE; PROTEINS; PROTEOLYSIS; VIRUSES

Citation Formats

Schlax, Peter E., Zhang Jin, Lewis, Elizabeth, Planchart, Antonio, and Lawson, T. Glen. Degradation of the encephalomyocarditis virus and hepatitis A virus 3C proteases by the ubiquitin/26S proteasome system in vivo. United States: N. p., 2007. Web. doi:10.1016/j.virol.2006.10.043.
Schlax, Peter E., Zhang Jin, Lewis, Elizabeth, Planchart, Antonio, & Lawson, T. Glen. Degradation of the encephalomyocarditis virus and hepatitis A virus 3C proteases by the ubiquitin/26S proteasome system in vivo. United States. doi:10.1016/j.virol.2006.10.043.
Schlax, Peter E., Zhang Jin, Lewis, Elizabeth, Planchart, Antonio, and Lawson, T. Glen. Tue . "Degradation of the encephalomyocarditis virus and hepatitis A virus 3C proteases by the ubiquitin/26S proteasome system in vivo". United States. doi:10.1016/j.virol.2006.10.043.
@article{osti_20977011,
title = {Degradation of the encephalomyocarditis virus and hepatitis A virus 3C proteases by the ubiquitin/26S proteasome system in vivo},
author = {Schlax, Peter E. and Zhang Jin and Lewis, Elizabeth and Planchart, Antonio and Lawson, T. Glen},
abstractNote = {We have isolated stably transfected mouse embryonic fibroblast cell lines that inducibly express either the mature encephalomyocarditis virus (EMCV) or hepatitis A virus (HAV) 3C protease and have used these cells to demonstrate that both proteins are subject to degradation in vivo by the ubiquitin/26S proteasome system. The detection of 3C protease expression in these cells requires inducing conditions and the presence of one of several proteasome inhibitors. Both 3C proteases are incorporated into conjugates with ubiquitin in vivo. HAV 3C protease expression has deleterious effects on cell viability, as determined by observation and counting of cells cultured in the absence or presence of inducing conditions. The EMCV 3C protease was found to be preferentially localized to the nucleus of induced cells, while the HAV 3C protease remains in the cytoplasm. The absence of polyubiquitinated EMCV 3C protease conjugates in nuclear fraction preparations suggests that localization to the nucleus can protect this protein from ubiquitination.},
doi = {10.1016/j.virol.2006.10.043},
journal = {Virology},
number = 2,
volume = 360,
place = {United States},
year = {Tue Apr 10 00:00:00 EDT 2007},
month = {Tue Apr 10 00:00:00 EDT 2007}
}
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