The Golgi apparatus, also known as the Golgi body is an organelle found in most eukaryotic cells. In 1897, the Italian physician Camillo Golgi identified this organelle, and the Golgi apparatus is named after him. The Golgi apparatus is surrounded by several small, membrane-bounded vesicles and the function of its vesicles in the modifying, sorting, and packaging of macro-molecules that are being secreted by the cells or are used for various functions within the cell.
Golgi Apparatus Structure
The Golgi apparatus is a complex structure that is composed of numerous layers of fluid-filled membrane sacs, also known as cisternae, which are arranged like stacked pancakes near the outer edges of the endoplasmic reticulum, ER, located near the nucleus. This organelle is organized into three biochemically distinct compartments which are: the medial Golgi, the cis Golgi and the trans Golgi; wherein the cis Golgi is the closest to the ER.
Golgi Apparatus Function
The basic Golgi apparatus is to process, modify and sort the newly produced proteins that will arrive from the endoplasmic reticulum. Such modifications are composed of adding and deleting certain molecules of sugar to change the branched sugar structures found on the proteins that are newly formed. For instance, few of the mannose sugars are cut from the cis Golgi’s oligosaccharide branch. Once this step is completed, the protein will travel to the medial Golgi where the other sugars such as fucose and N-acetylglucoseamine are added to the oligosaccharide branches on the protein. Other carbohydrate alterations are completed in the trans Golgi. Addition of carbohydrates can aid in the transport, stability and function of the proteins.