2013 Group 3 Project

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Diagram of the Golgi Apparatus

The Golgi apparatus is a relatively large, membrane-bound organelle and thus one of the easiest cell structures to study in detail [2]. The organelle is located nearby the cell nucleus and is closely associated with the endoplasmic reticulum. By observing via metallic impregnation, it can be seen through phase contrast microscopy that the Golgi has a convoluted, dense and “ill-formed” morphology [3]. Initial studies have shown that the organelle has great variance in its form dependent on the type of cell it is in as well as the state of activity that the cell is in. There are roughly around 40-100 Golgi apparatus ‘stacks’ within a mammalian cell [4].

Overall, the Golgi apparatus is made of 4-8 flattened, membrane-bound sacs that are stacked upon one another [5]. These are known as cisternae. The Golgi also includes associated nearby vesicles. Each cisterna primarily contains products from the endoplasmic reticulum, which enter the Golgi at the cis face – the end that is closest to the ER and accepts incoming vesicles [6]. The cis face is where new cisternae are formed. The products eventually pass through two more functional regions (medial Golgi and endo Golgi networks) and then are exported via outgoing vesicles at the trans face of the organelle. The trans face is where formed proteins are sent off and is the face furthest away from the ER. There is a constant and relatively consistent distance kept between cisternae of the Golgi apparatus [5].


Golgi apparatus is considered to be essential membrane-bound organelle in eukaryotic cells that sums all plant, animal and fungi life [7]. It's physical structure is a composition of dozens of flattened cristernae that has been brought together and flattened with fenestrated rims. Golgi has a primary function of modifying and packaging proteins and lipids into several transport carriers to be able to send them to their proper locations. Proteins such as secretory or trans-membrane proteins are delivered from the endoplasmic reticulum (ER) to the cis-Golgi network. Consequently, the Golgi act as a series of transportation canal where cargo molecules travel via different Golgi cristernae where residential enzymes modify and post-transitionally process them.

Behavior of the Golgi during Mitosis

During mitosis, the Golgi can undergoes one of two courses, depending on wether it is from an animal cell or a plant or yeast cell. In animal cells, it completely disintegrates and separates. The cisternae stacks come apart and move away from one another. However in plant or yeast cells, the Golgi remains together. It is just before cytokinesis (during telophase) that the parts of the Golgi reassemble and from an intact organelle (in plant cell mitosis).


It was once theorised that the Golgi apparatus could be formed de novo within daughter and mitotic cells. It has since been discovered that in animal cells, the organelle cannot be synthesised de novo and thus, must divide when a cell divides [9]. Through cytochemical and immunofluorescence light microscopy, it has been shown that the Golgi would undergo breakdown early on in mitosis, giving rise to many Golgi fragments [10]. These fragments (in the form of small tubules and vesicles) would be dispersed throughout the cytoplasm at random. The partitioned Golgi would segregate into even groups and end up in the daughter cells to serve as a template to new Golgi apparatuses[11].


How does the Golgi differ from other organelles?

Where GA is located in cells


Stained Golgi.png The relationship between the Golgi and microtubules.png

Morphology of GA prior to cell division


flattened membrane-bound structures approxi- mately 1 m m long, also termed Golgi cisternae. Between two and five cisternae are aligned in a parallel manner to form a Golgi stack.

The Golgi stacks are polarized in a cis / trans fashion

morphology during each part of cell divisions





how the above process differs in other organisms

limitations of current models





  1. <pubmed>PMC2106267</pubmed>
  2. <pubmed>9865849</pubmed>
  4. <pubmed>18385516</pubmed>
  5. 5.0 5.1 <pubmed>19866649</pubmed>
  7. <pubmed>21646379</pubmed>
  8. <pubmed>PMC25291</pubmed>
  9. <pubmed>519753</pubmed>
  11. <pubmed>12851069</pubmed>
  12. <pubmed>15695096</pubmed>


Golgi Apparatus Maintains Its Organization Independent of the Endoplasmic Reticulum

Partitioning of the Golgi Apparatus during Mitosis in Living HeLa Cells

Golgi biogenesis

