Question

What is the purpose of C-peptide in proinsulin?

• A. To extend the insulin molecule
• B. To bring A and B chain in correct orientation to form active insulin
• C. To remove N terminal signal peptide
• D. To bind to the glucose molecule

Answer 1

The correct option is B To bring A and B chain in correct orientation to form active insulin

Proinsulin when produced naturally, has an N terminal signal peptide, A and B chain, and a C peptide. The C peptide is required for forming correct three dimensional structure of active insulin by bringing A and B chains in correct orientation. In the formation of mature insulin, the C peptide is edited out after disulphide linkages are formed between the A and B chains.