What is an endosome?
a membrane-bounded compartment inside eukaryotic cells
What happens in exocytosis?
Where a transport vesicle fuses with the plasma membrane and its contents are released into the extracellular space, while the vesicle becomes continuous with the plasma membrane.
What happens in endocytosis?
Where a plasma membrane patch is internalised forming a transport vesicle, the contents being derived from the extracellular space.
What are the three types of endocytosis?
- phagocytosis
- pinocytosis
- receptor-mediated cytosis
How do vesicles know where to go?
Molecular markers on the cytosolic surface
What are the three types of coated vesicles?
- Clathrin-coated
- COPI-coated
- COPII-coated
What structures do clathrin-coated vesicles transport between?
- Golgi to endosomes
- Membrane to endosomes
What structures do COPI-coated vesicles transport between?
- Golgi and ER
- Golgi and plasma membrane
What structures do COPII-coated vesicles transport between?
- Between the ER and golgi
What are adaptor proteins?
Another major coat component in clathrin-coated-vesicles that form a layer between the clathrin-coat and the cell membrane
What do **adaptor **proteins do?
Capture transmembrane proteins that can transport cargo into the vesicle
What controls recognition of membranes?
SNARES:
- V-SNARES (vesicles)
- T-SNARES (target)
Recognition of target membranes is assisted by what enzyme?
Rab GTPases
In what type of coat does a vesicle leave the ER in?
COPII
What are some of the modifications the golgi apparatus carries out?
What are the three options of transport from the golgi?
- Late endosomes
- Direct non-specific transport to cell surface
- Specific transport to cell surface via secretory vesicles
What are the two secretory pathwatys?
Constitutive and regulated
What are the three pathways to form lysosomes?
- phagocytosis
- endocytosis
- autophagy
