Final answer:
The false statement is that some proteins are folded only by HSP-60 and do not need HSP-70(option 2). Both types of heat shock proteins, HSP-60 and HSP-70, function in the protein folding process at different stages, and chaperones are critical for proper protein folding, especially under stress conditions.
Step-by-step explanation:
False Statement About Chaperones
The false statement about chaperones in the options provided is: "Some proteins are folded only by HSP-60 and do not need HSP-70." This is not accurate as proteins can require different types of heat shock proteins (HSP) such as HSP-60, known as chaperonins, and HSP-70, which both play distinct roles in the folding process of proteins. While HSP-70 binds to nascent polypeptide chains as they emerge from the ribosome, preventing premature folding or aggregation, HSP-60 typically acts later, assisting in the correct folding after the protein has been synthesized completely.
It is true that most proteins need the assistance of chaperones to fold inside the cell, and HSP-70 binds to proteins as they are being synthesized by the ribosome. Also, HSP-60 binds to proteins after they have been completely synthesized. Chaperone proteins, including HSP-70, are important for preventing incorrect folding and aggregation, especially under stress conditions such as high temperatures or abnormal pH levels that can adversely affect the folding process. Moreover, cells respond to stress such as heat shock by increasing the activity and production of heat shock proteins to refold misfolded proteins thus maintaining protein homeostasis. The dynamic action of chaperone proteins is critical for the proper functioning of cellular proteins.