| Comments |
P.341 left column top paragraph: "Additionally, PN regulation is integrated with pathways involved in inflammation, response to oxidative stress, caloric restriction/starvation, and longevity. The PN of mammalian cells consists of ∼1,300 different proteins involved in protein biogenesis (∼400), conformational maintenance (∼300), and degradation (∼700), with many proteins being part of more than one pathway (Figure 8b). Different cell types vary in their proteostasis capacity and thus in their stress sensitivity and vulnerability to protein aggregation (refs 194, 195)." P.341 right column top paragraph: "Degradation: A central feature in the organization of the PN is the tight interconnection of molecular chaperone functions with the pathways of protein degradation, which serve to remove nonfunctional, misfolded, or aggregated proteins that may otherwise disrupt proteostasis. The PN branch of degradation includes the ubiquitin-proteasome system (UPS) and machinery of autophagy (ref 23, refs 196-200). Approximately 700 proteins are implicated in protein degradation, reflecting the fundamental importance of these pathways in cell regulation and protein homeostasis." |