What is a key function of the Golgi apparatus besides packaging proteins?

The Golgi apparatus plays a critical role in processing proteins that have been synthesized in the endoplasmic reticulum. While it is well-known for packaging and distributing proteins, a key function of the Golgi apparatus is modifying and sorting these proteins. This involves adding carbohydrates, lipids, or phosphate groups to form glycoproteins and glycolipids, which are important for various cellular functions and duties.

After these modifications, the Golgi apparatus then sorts and directs the proteins to their appropriate destinations within or outside of the cell. This sorting is crucial for ensuring that proteins reach the right cellular compartments or are secreted out of the cell to perform their functions. Without this capability, proteins could end up in the wrong location, leading to dysfunctional cellular operations or diseases.

While protein synthesis occurs in the ribosomes and detoxification is primarily associated with the smooth endoplasmic reticulum or liver cells, and lipid storage pertains to other cellular structures like lipid droplets, these processes are distinct from the primary activities of the Golgi apparatus.