Facilitator Questions

1. As we have seen in the lecture, cells contain many different membrane-bound structures, from the endoplasmic reticulum and Golgi apparatus to digestive organelles like the yeast vacuole and animal lysosome. How does this internal organization of membranes benefit the cell? How does it relate to vesicular transport?

 

2. Why do you think vesicles in nerve cells are targeted to the plasma membrane prior to receiving a stimulus? How might this be beneficial to the cell and its neighbors?

 

3. Can any part of a secretory vesicle be recycled once it has fused with the plasma membrane? If so, how might this benefit the cell?

 

4. What does it mean to say that membrane fusion event between vesicles and the plasma membrane (involving Sec1p in yeast) is a “fundamentally conserved process?” How was this determined?

 

5. Describe the three distinct secretory mutant phenotypes that were discussed in lecture and explain which station of the secretory pathway each is associated with. How does the double mutant analysis of these phenotypes reveal the correct forward flow of material (ER to Golgi to plasma membrane) through the secretory pathway in yeast?