Figure 8. A proposed role of stress- and p53-induced BAG5. A schematic diagram shows that stress induces BAG5 expression through p53 binding at the BAG5 promoter. Under slight stress, a low level of BAG5 improves protein refolding efficiency by acting as a nucleotide exchange factor of HSP70. When the stress is too high, overexpressed BAG5 may accelerate the release of rashly folded clients from the substrate-binding domain (SBD) of HSP70, which causes unfolded protein aggregation.