Protein sorting in the Golgi

Many different proteins are synthesized on the rough endoplasmic reticulum (RER) and transported to the Golgi apparatus in transport vesicles. From the Golgi apparatus these proteins are then sent to their proper locations in the cell. For example:

To insure that these different proteins are sent to their proper locations, they must be sorted, one from the other, in the Golgi apparatus. Thus one function of the Golgi apparatus is protein sorting.

In the following diagram the Golgi apparatus is indicated and in the lumen of the Golgi are different proteins indicated by the red, green and blue dots. The different proteins are intermixed in the Golgi but are sorted from each other before they are packaged into vesicles.


Protein glycosylation in the Golgi

There are many different way inwhich proteins are modified in the Golgi apparatus. One very well studied way involves the addition of carbohydrtes to proteins.

The lumen of the golgi apparatus has enzymes that will covalently bond carbohydrates to proteins.