How do proteins enter peroxisomes?: (A) Folded, using a C-terminal or internal signal sequence, (B) Folded, using an N-terminal or internal signal sequence, (C) Unfolded, using a C-terminal or internal signal sequence, (D) Unfolded, using an N-terminal or internal signal sequence
Answer is A. Peroxisomal proteins are fully folded in the cytoplasm and enter the organelle in folded form. The most common signal sequence which directs proteins to peroxisomes is a C-terminal Ser-Lys-Leu tripeptide. Reference: Harper; 30th edition