The key difference between cisternal maturation and vesicular transport is that in cisternal maturation, new cis cisterna forms, matures, and then, carries secretory cargos forward while, in vesicular transport, secretory cargos move forward across stable and distinct cis, medial and trans-Golgi stack by the vesicles budded off from each cisterna.
The Golgi complex is one of the most vital cell organelles of the eukaryotic cells. It fulfils a major function in the secretory pathway in terms of sorting and sequential processing of a large number of proteins. Cisternal maturation and vesicular transport are two pathways in the Golgi complex that helps to move secretory cargos inside the cell. Hence, this article attempts to describe the difference between cisternal maturation and vesicular transport.
CONTENTS
1. Overview and Key Difference
2. What is Cisternal Maturation
3. What is Vesicular Transport
4. Similarities Between Cisternal Maturation and Vesicular Transport
5. Side by Side Comparison – Cisternal Maturation vs Vesicular Transport in Tabular Form
6. Summary
What is Cisternal Maturation?
Cisternal maturation is a pathway of moving secretory cargos by the Golgi complex, from the endoplasmic reticulum (ER) to cell membrane. Cisternae themselves act as transient carriers in this model. Vesicles move in a retrograde manner towards the cis Golgi. Most importantly, vesicles do not carry proteins that came from the ER. Instead, Golgi stack moves, carrying newly made proteins of ER. New cis cisterna forms carrying the proteins. Then it matures into medial Golgi and later into trans Golgi. Then trans-Golgi delivers the proteins to the cell membrane. Likewise, in this pathway, a new Golgi cisterna forms at the cis face. And, it then moves forward in the stack as the enzyme content of the cisterna changes from cis to medial to trans.
What is Vesicular Transport?
Vesicular transport is one of the mechanisms used by the Golgi complex to deliver proteins from the ER to the cell membrane. This pathway operates via cis, medial and trans-Golgi compartments. The vesicles bud off from the rough ER fuse with the cis Golgi compartment. Then, a vesicle containing the proteins to be secreted buds off from the cis Golgi compartment towards the medial Golgi compartment. The vesicle fuses with the medial Golgi compartment and then it buds off towards the trans-Golgi compartment. From the trans-Golgi compartment, a vesicle buds off towards the cell membrane carrying the proteins. Likewise, secretory cargos move across the Golgi stack via cis, medial and trans compartments via vesicles.
Figure 01: Vesicular Transport
Vesicular transport is mainly important for transporting receptor proteins from the ER to the cell membrane. Most importantly, in this method, resident Golgi proteins stay in place without being excluded via budding vesicles.
What are the Similarities Between Cisternal Maturation and Vesicular Transport?
- Cisternal maturation and vesicular transport are two types of mechanisms which transport proteins from the ER to cell membrane via Golgi complex.
- Moreover, three types of cisterns participate in both processes.
What is the Difference Between Cisternal Maturation and Vesicular Transport?
Cisternal maturation is a mechanism in which cisternae themselves act as carriers of newly made proteins of the ER to the cell membrane. On the other hand, vesicular transport is another mechanism in which vesicles carry newly made protein of the ER to the cell membrane. So, this is the key difference between cisternal maturation and vesicular transport.
Moreover, a further difference between cisternal maturation and vesicular transport is the carrying of newly made proteins. Cisternae carry the secretory cargos forward in cisternal maturation while the vesicles carry the secretory cargos forward in vesicular transport. Besides, budding off of resident Golgi proteins does not occur in vesicular transport, while it occurs in cisternal maturation. Hence, this is also a difference between cisternal maturation and vesicular transport.
Furthermore, in cisternal maturation, vesicles do not carry newly made proteins while vesicles carry the newly made proteins in the vesicular transport. Another difference between cisternal maturation and vesicular transport is the movement of vesicles. In cisternal maturation, vesicles move in a retrograde manner while in vesicular transport, vesicles move towards the trans-Golgi.
Summary – Cisternal Maturation vs Vesicular Transport
Cisternal maturation and vesicular transport are two models that explain the transport of proteins from the ER to cell membrane by the Golgi complex. As the names suggest, in cisternal maturation, new cis Golgi cisterna forms, matures into medial and trans cisternae, and carries proteins from ER to cell membrane while, in vesicular transport, vesicles formed and budded off from each cistern carry the newly made proteins from ER to the cell membrane. Thus, this is the key difference between cisternal maturation and vesicular transport. Most importantly, cisternae move during cisternal maturation while cisternae remain stationary in vesicular transport.
Reference:
1. Glick, Benjamin S, and Alberto Luini. “Models for Golgi Traffic: a Critical Assessment.” Cold Spring Harbor Perspectives in Biology, Cold Spring Harbor Laboratory Press, Available here.
Image Courtesy:
1. “Nucleus ER golgi ex” By Magnus Manske (Public Domain) via Commons Wikimedia