Question 1: Suppose that an operon that exhibited positive control was inducible. Would the regulator gene in this case produce an active or an inactive activator protein? What would most likely turn transcription on? What about an operon with positive control that was repressible? In this case, what would turn transcription off? Explain your reasoning.
Question 2: What would be the effect on tryptophan production of mutations in region 1 of the leader of the trp operon that changed the Trp codons to stop codons? Explain your reasoning.
Question 3: Mutations in genes encoding chromatin-remodeling complexes have been identified in high frequencies in some human cancers. For example, mutations in components of the human SWI-SNF remodeling complex were found in 19% of tumors in a group of cancers. How might a mutation in a chromatin-remodeling complex contribute to cancer?
Question 4: What changes take place in chromatin structure, and what role do these changes play in eukaryotic gene regulation?
Question 5: Briefly explain how transcription factors affect the level of transcription of eukaryotic genes.