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Title: Changes of Protein Turnover in Aging Caenorhabditis elegans

Abstract

Protein turnover rates severely decline in aging organisms, including C. elegans. However, limited information is available on turnover dynamics at the individual protein level during aging. We followed changes in protein turnover at one-day resolution using a multiple-pulse 15Nlabeling and accurate mass spectrometry approach. Forty percent of the proteome shows gradual slowdown in turnover with age, whereas only few proteins show increased turnover. Decrease in protein turnover was consistent for only a minority of functionally related protein subsets, including tubulins and vitellogenins, whereas randomly diverging turnover patterns with age were the norm. Our data suggests increased heterogeneity of protein turnover of the translation machinery, whereas protein turnover of ubiquitin-proteasome and antioxidant systems are well-preserved over time. Hence, we presume that maintenance of quality control mechanisms is a protective strategy in aging worms, although the ultimate proteome collapse is inescapable.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1406683
Report Number(s):
PNNL-SA-129634
Journal ID: ISSN 1535-9476; 49531; 453040220
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Molecular and Cellular Proteomics; Journal Volume: 16; Journal Issue: 9
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Dhondt, Ineke, Petyuk, Vladislav A., Bauer, Sophie, Brewer, Heather M., Smith, Richard D., Depuydt, Geert, and Braeckman, Bart P.. Changes of Protein Turnover in Aging Caenorhabditis elegans. United States: N. p., 2017. Web. doi:10.1074/mcp.RA117.000049.
Dhondt, Ineke, Petyuk, Vladislav A., Bauer, Sophie, Brewer, Heather M., Smith, Richard D., Depuydt, Geert, & Braeckman, Bart P.. Changes of Protein Turnover in Aging Caenorhabditis elegans. United States. doi:10.1074/mcp.RA117.000049.
Dhondt, Ineke, Petyuk, Vladislav A., Bauer, Sophie, Brewer, Heather M., Smith, Richard D., Depuydt, Geert, and Braeckman, Bart P.. Wed . "Changes of Protein Turnover in Aging Caenorhabditis elegans". United States. doi:10.1074/mcp.RA117.000049.
@article{osti_1406683,
title = {Changes of Protein Turnover in Aging Caenorhabditis elegans},
author = {Dhondt, Ineke and Petyuk, Vladislav A. and Bauer, Sophie and Brewer, Heather M. and Smith, Richard D. and Depuydt, Geert and Braeckman, Bart P.},
abstractNote = {Protein turnover rates severely decline in aging organisms, including C. elegans. However, limited information is available on turnover dynamics at the individual protein level during aging. We followed changes in protein turnover at one-day resolution using a multiple-pulse 15Nlabeling and accurate mass spectrometry approach. Forty percent of the proteome shows gradual slowdown in turnover with age, whereas only few proteins show increased turnover. Decrease in protein turnover was consistent for only a minority of functionally related protein subsets, including tubulins and vitellogenins, whereas randomly diverging turnover patterns with age were the norm. Our data suggests increased heterogeneity of protein turnover of the translation machinery, whereas protein turnover of ubiquitin-proteasome and antioxidant systems are well-preserved over time. Hence, we presume that maintenance of quality control mechanisms is a protective strategy in aging worms, although the ultimate proteome collapse is inescapable.},
doi = {10.1074/mcp.RA117.000049},
journal = {Molecular and Cellular Proteomics},
number = 9,
volume = 16,
place = {United States},
year = {Wed Jul 05 00:00:00 EDT 2017},
month = {Wed Jul 05 00:00:00 EDT 2017}
}
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