Proteostasis is essentially the overall ‘management’ of proteins by the cell, including building them correctly when they are needed, their continued maintenance, shuttling them around the cell and recycling/destroying them once they’ve become too damaged to do their job properly. Loss of proteostasis is a hallmark of aging, and refers to the decline in ability of cells to properly manage their proteins. In particular, cells become less able to repair dispose of damaged and potentially harmful proteins, such as those that have unfolded. The accumulation of such proteins is associated with many age-related diseases and processes, most famously neurodegenerative diseases like Alzheimer’s. A more detailed explanation of proteostasis can be found in this article.
The potential fates of an unfolded protein: misfolding and aggregation; refolding by chaperone proteins; degradation by proteosome; degradation by lysosome.
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