Biology 2nd Edition by Robert Brooker, Eric Widmaier ,Linda Graham ,Peter Stiling

Exercise 11

Let's suppose an abnormal protein contains three targeting sequences: an ER signal sequence, an ER retention sequence, and a mitochondrial matrix-targeting sequence. The ER retention sequence is supposed to keep proteins within the ER. Where would you expect this abnormal protein to go Note: Think carefully about the timing of events in protein sorting and which events occur cotranslationally and which occur post-translationally.
A) It would go to the ER.
B) It would go the mitochondria.
C) It would go to both the ER and mitochondria equally.
D) It would remain in the cytosol.
E) It would be secreted.