New insights into old worm proteomes.

Aging is accompanied by large-scale changes in the proteome, which could have important consequences for cellular and organismal physiology. In this commentary, we review recent studies characterizing the aging proteome in C. elegans. We assess the evidence that the rates of protein synthesis, folding, and degradation change with age in C. elegans, and evaluate whether changes in these pathways limit normal lifespan. We also discuss large-scale studies measuring changes in the proteome with age that suggest that a failure to excrete reproductive proteins in post-reproductive animals plays a role in changing protein levels with age.