Summary
Coat proteins and SNARE complexes sort, bud and fuse vesicles to move cargo between membrane compartments.
In depth
Cargo is concentrated into buds coated with COPII (ER to Golgi), COPI (back to ER) or clathrin (from Golgi and plasma membrane). Rab GTPases identify the vesicle's destination and v-SNAREs on vesicles pair with t-SNAREs on targets, pulling the membranes together to fuse.
This ensures vesicles deliver to the correct compartment and keep organelle identity. Botulinum toxin cuts SNAREs and blocks neurotransmitter release.
The pathway can be summarised as: ER, COPII vesicle, ER-Golgi intermediate compartment, Golgi cisternae, trans-Golgi network, then onward to the plasma membrane, endosomes or lysosomes. Retrieval signals such as KDEL keep ER-resident proteins in place by returning escapers from the Golgi.
Fusion needs SNARE complexes that twist into a four-helix bundle, with NSF and SNAP proteins later recycling them. Randy Schekman, James Rothman and Thomas Sudhof shared the 2013 Nobel Prize for revealing this machinery.
Example: in cystic fibrosis the most common CFTR mutation causes the protein to be recognised as misfolded and held back in the ER, so it never reaches the surface.
Frequently asked questions
What is Vesicle Trafficking?
Coat proteins and SNARE complexes sort, bud and fuse vesicles to move cargo between membrane compartments.
Which area of biology covers Vesicle Trafficking, and how advanced is it?
Vesicle Trafficking is one of the 52 topics in Cell Biology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Exocytosis, Signal Recognition Particle, Nuclear Pore Complex.
Can you give an example of Vesicle Trafficking?
Randy Schekman, James Rothman and Thomas Südhof won a Nobel Prize in 2013 for discovering these mechanisms.
What should I learn before Vesicle Trafficking?
Work through the Beginner topics in Cell Biology first, such as Cell Theory, Prokaryotic Cell, Eukaryotic Cell, then return to Vesicle Trafficking. Advanced topics assume the Intermediate vocabulary.
What topics are related to Vesicle Trafficking?
The closest topics to Vesicle Trafficking are Exocytosis, Signal Recognition Particle, Nuclear Pore Complex, Autophagy. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Vesicle Trafficking?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Vesicle Trafficking. To practise the whole of Cell Biology, use the Cell Biology quiz.
How is Vesicle Trafficking different from Exocytosis?
Vesicle Trafficking: Coat proteins and SNARE complexes sort, bud and fuse vesicles to move cargo between membrane compartments. Exocytosis: Vesicles fuse with the plasma membrane to release their contents outside the cell. Read both side by side and note what each one explains.
How should I study Vesicle Trafficking step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Exocytosis and explain the difference aloud. Finally, take the Cell Biology quiz and come back to this page for any question you miss.