Eukaryotes protein sorting signals

All eukaryotic cells possess an unspecialized exocytic pathway known as the constitutive secretion. Vesicle membranes in this pathway fuse with the plasma membrane without any extracellular signal. As noted above, proteins destined for the secretory pathway are sorted at the level of the TGN. Proteins to be transported to the plasma membrane are directed into a constitutive secretory pathway. 

---