|MadSci Network: Biochemistry|
Jonathon, I'm going to give you an answer, not to this question, but to the general class of questions like this one.
Whenever I have a question, and I don't even understand what the question is asking, it's usually because I don't understand the relationship of the important terms in the question to one another. Here's what I do:
Search Wikipedia for the terms in the question that you don't understand the meaning of, such as farnesyltransferase, GTPase, and Ras. Sometimes when Google is no help, Wikipedia works better. You can also try Pubmed, but you may not be able to access some information unless you're at your college library. Read those pages until you know what the meaning of any unfamiliar terms in the question are. Ask yourself how the given information is relevant to the question as you understand it.
We can see how this process works with the question you were given. The wikipedia page for farnesyltransferase talks about what they are, mentions farnesyltransferase inhibitors in the first paragraph, and in the same sentence with Ras and GTP-binding proteins. Let's follow that link. Here it talks about FTIs and their function with regards to the Ras protein. Now, you can follow the link to Ras to read about how Ras proteins work. Understanding how Ras proteins work, what they do, and what has to happen for them to do what they do, we can try to restate the question in a form that's easier to understand.
So, you've got a mutant protein that binds Ras, and as a result, you've got Ras binding GTP at a much higher level than normally. You know from the reading in wikipedia that farnesyltransferase inhibitors prevent Ras from being active.
Now the question is easier to understand: What proteins usually bind Ras, and what would the effect of mutating of of those proteins have on the GTP-binding ability of Ras? What effect would an alteration of GTP-binding have, considering the biological activity of Ras? How would a farnesyltransferase inhibitor counteract the effect of this altered function?
Let me caution you about relying to heavily upon wikipedia, because while it is usually a great source of information, the information it contains can be highly biased, opinionated, or just plain wrong.
Try the links in the MadSci Library for more information on Biochemistry.