A diverse group of proteins, nearly all of which are synthesized on the rough endoplasmic reticulum, cotranslationally transported into the lumen of the endoplasmic reticulum (see signal recognition particle) and then moved, via the Golgi, to secretory vesicles. The majority are glycosylated. There are few exceptions; some are not glycosylated, others (e.g. collagen) do not go through the same processing pathway. In prokaryotes, secreted proteins may be synthesized on ribosomes associated with the plasma membrane or exported from the cytoplasm after translation has been completed.
Subjects: Medicine and Health.