How do all the organelles of the endomembrane system work together to perform produce, package, and secrete?

Hi Victoria,

Firstly, a primary-structured protein is translocated into the lumen of the rough endoplasmic reticulum from ribosomes which are temporarily attached through pores called translocons. Withinthe lumen of this organelle, the protein will fold into its tertiary structure and be packaged into a vesicle as the protein exits the rER.

Then, the protein will travel to and fuse with the cis (first) cisterna and, within, the protein will be modified (e.g. glycosylated). Then, vesicles will bud off of the trans (final) cisterna. The vesicle will be modified to become clathrin-coated (for lysosome formation) or COP II-coated (for secretion and exocytosis out of the cell) or COP I-coated for transport back to the rough endoplasmic reticulum for intracellular use or further intracellular transport among the endomembrane system.

Hope this helps :)