13. You are trying to identify genes that are involved in pyrimidine synthesis in yeast using a forward genetic approach.
• How would you go about this?
• Using the results from the above experiments, how do you characterize these genes molecularly using a reverse genetic approach?
• In the above experiment you identify several genes that encode for different enzymes involved in a metabolic pathway, which you order using epistasis analysis. However, during these experiments you find that loss-of-function mutations of one particular gene lead to a loss of expression of most of the enzyme-coding genes. What is your interpretation of this result concerning the role and molecular identity of this gene? What is your prediction, and how would you test your hypothesis?