Analysis of mutants


How would you would isolate and analyze (a) structural gene mutations, and (b) regulatory gene mutations of a biosynthetic pathway in Neurospora or yeast.


What questions would occur to you if you isolated a pleiotropic mutant that expressed multiple genes at high constitutive levels? What questions would occur to you if you isolated a pleiotropic negative mutant [i.e., a mutant that fails to express multiple genes]?


What is the predicted phenotype of a mutation in a negative regulatory system?


What is the predicted phenotype of a mutation in a positive regulatory system?


Given genetic data suggesting a mutation in a positive regulatory gene, what experiments could you do to confirm this hypothesis? [What alternatives explanations would you need to exclude?]


What can analysis of double mutants tell you about regulatory cascades?


What data are needed to define a presumptive promoter mutant?


If you isolated a transposon insertion mutation in a positive operator site for an operon, what would the regulatory phenotype be?


Compare feedback inhibition with post-translational modification. How do both of these controls differ from transcriptional and translational controls?


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Last modified October 30, 2003