ABSTRACT
In yeast and animal cells, secretory proteins are synthesized on ribosomes bound to the endoplasmic reticulum (ER), from where they are subsequently translocated into the lumen of the ER by a signal sequence/receptor-mediated mechanism. In the ER, they undergo co-and post-translational modifications. Due to the number of processes occurring in the ER and their importance to protein secretion, this organelle has been considered as most important for determination of the "quality" and the "fate" of secreted proteins.
