What is the main role of the golgi?

The way that proteins move through the golgi has long been a source of contention. Two major models have been proposed. One is a cisternal maturation model, and the other is a model of stable cisternae and mostly vesicular transport. In this paper they set out to try and differentiate these models using a modified Golgi resident protein.

In this paper they talk a bit about Golgi Tubules, these are like vesicles but form as long tubes rather then little circles… don’t worry too much about this issue.

Intro Questions (from last weeks panopto’s and the intro of the paper)

1) What is the main role of the golgi? How do the processes that are occurring differ from one stack to another (in other words, why have different stacks) – what is happening to proteins in these stacks?

2) What are the two main models of Golgi maturation? What is the different between Golgi resident proteins, and proteins moving through the endomembrane system? How would you expect the paths of these two protein types to be different?

Figure Questions:

Figure 1: What is Mani? How is Mani-FM different, and what is happening to Mani-FM when they add AP what about when AP is absent? What is the pellet vs supernatant test telling them?

Figure 2: What is Figure 2 showing them? Why did they do this test?

Figure 3: What are the main findings of figure 3?

Figure 4 a-i : What do they find about the localization of MANI-FM with and without AP within the golgi? Which of the two mechanisms of golgi maturation does this support?

Figure 4 j&k – what does this tell them about Mani-Fm with and without AP?

Figure 5: How is what they are doing in this figure different from what they did in Figure 4? What is this showing them? What did the washout tell them that the initial application did not? Given your knowledge of golgi trafficking, what kind of vesicles would you expect to fine Mani-FM in?

Conclusion Questions: What are the overall conclusions from the paper? Which model of Golgi trafficking does this support? Why is this interesting to us?

More Challenging questions: How are there findings different from previous work? What did they show that no-one has showed about this model before?

Be sure to include a bibliography of your sources.