Question

What does chaperones assist in?

• A. Protein Cleavage
• B. Protein Folding
• C. Protein Degradation
• D. Protein Modification

Answer 1

The Correct Option is B

Step 1: Consider what a fresh polypeptide faces as it leaves the ribosome. Its exposed hydrophobic stretches could clump together and misfold before it reaches its proper shape.

Step 2: Chaperones step in to guard the chain, binding and releasing it, often using $ATP$, so it can settle into the correct native fold without aggregating. Therefore their role is protein folding.

Step 3: Familiar examples are the heat shock proteins, including Hsp70 and the chaperonin Hsp60 system, which actively promote correct folding in vivo.

Step 4: The wrong answers belong to other machinery: proteases and the proteasome handle cleavage and degradation, and dedicated transferases handle covalent modification, none of which is the chaperone function.

\[\boxed{\text{Protein folding}}\]