How Are Secretory Proteins Made?

Secretory proteins are synthesized by ribosomes attached to the cisternae of the endoplasmic reticulum and translocated to the lumen of the endoplasmic reticulum.

Where are secretory proteins packaged?

Thus, by the time the protein achieves its final form, it is already inserted into a membrane (Figure 1). The proteins that will be secreted by a cell are also directed to the ER during translation, where they end up in the lumen, the internal cavity, where they are then packaged for vesicular release from the cell.

What secretes proteins from the cell?

The secretory pathway refers to the endoplasmic reticulum, Golgi apparatus and the vesicles that travel in between them as well as the cell membrane and lysosomes. It's named 'secretory' for being the pathway by which the cell secretes proteins into the extracellular environment.