Topic 7: Vesicular Transport and the role of the Golgi Flashcards
WHat is the order of passing from the ER out to the rest of the cell? what structures must these proteins pass through?
ER to the ER-Goldi intermediate compartment to the Golgi
Not all proteins pass all the way through, vesicles carry through this pathway.
Can you describe the structure of the Golgi apparatus?
Stacks of sacks called cisternae that are no continuous. Cis face recived from ERGIC. Medial cisternae are in the middle of the stack. Trans face faces away from RER towards cell surface. Trans golgi network receives from the trans face.
What aspect of the Golgi do newly translated proteins enter? What aspect do they exit?
Enter through the Cis face and elave through the trance face
What are 2 important lipids that are created in the golgi? Since made in the Golgi how does this determine their final destination?
Glycolipids and sphingomeylin
What is the difference between cisternal maturational model and the stable cisternae model?
Stable: Stacks stay put but send proteins from one stack to the next as proteins mature
Cisternal: The entire stacks will move from cis to trans maturing their proteins as they move
How do proteins either luminal or transmembrane travel from one organelle to the next? What about these travelning structres allow them to intergrate with a variety of different organelles?
Travel via vesicles, which more cargo and membrane-bound proteins between compartments within the cell. Vesicles must recognize and fuse only with the appropriate target membrane. Coats help them integrate within a variety of cells
What is a coat protein?
assemble in the cytosol causing vesicles to bud off and separate.
What about Clathrins shape allows it to perfrom its function? HOw does dynamin help clathrin?
Clathrin has a triskeleton shape base unit that induces curvature of the plasma membrane when it polymerizes. When vesicle is spherical and ready to bud, Dynamin comes in and pinches off the stalk to releases the vesicle into the cytosol.
Describe the roles of proteins in coating of clathrin?
COP II: carry proteins from ER to the ERGIC and on to the golgi apparatus
COP I bud from the ERGIC or golgi and carry their cargo back returning proteins to earlier compartments
Clathrin: Transport in both directions between the trans Golgi network endosomes, lysosomes and plasma membrane.
How does a vesicle fuse with the membrane of the target organelle or location?
What is KDEL?
What is the different between different “somes”?
Can you describe the constitutive regulated pathways?
What is autophagy?
