Changes of Protein Turnover in Aging Caenorhabditis elegans

N-labeling 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.