Final answer:
When misfolded proteins accumulate in a cell faster than they can be exported, it triggers the unfolded protein response, chaperones like HSP70 assist in folding, and diseases such as cancer can result. The Signal Hypothesis illustrates the normal route for export proteins but when overwhelmed, can contribute to disease.
Step-by-step explanation:
If misfolded proteins are generated faster than they can be exported, it potentially triggers a stress response in the cell known as the unfolded protein response (UPR). Chaperones like HSP70 help proteins fold correctly and maintain stability. When the cell's mechanisms for folding and exporting proteins are overwhelmed by an accumulation of misfolded proteins, it may lead to diseases such as cancer, where the accumulation of these proteins can contribute to uncontrolled cell growth, creating tumors.
Normal protein trafficking in a cell that synthesizes proteins for export involves the assistance of chaperone proteins. These proteins aid in the folding process, which is necessary for proper function. In certain stress conditions, such as abnormal temperature or pH, chaperones are essential in preventing incorrect folding or aggregation of developing proteins.
The Signal Hypothesis indicates that secreted proteins have a signal sequence that directs them to the rough endoplasmic reticulum (RER) for maturation and export. However, if misfolded proteins accumulate within the cell, the Signal Hypothesis is less effective, creating a bottleneck in protein traffic that can induce cellular stress responses.