Which of the following sequence is directed in a retrograde manner to EPR in COP-1 vesicles?: (A) KDEL, (B) KDAL, (C) DALK, (D) KDUL
Answer is A. KDEL sequence ( lysine - aspaate - glutamate - leucine ) at carboxy terminal first travel to GA in COP-2 vesicles, interact with their specific receptor protein. then they return in a COP-1 vesicle to EPR, get dissociate from their receptor & are retrieved. Reference: Harper; 30th edition