Microbiology - 0330 - Gene regulation

  1. negative control
    when something binds, the gene expression is turned off {all about repressor}
  2. eg of negative control
    • repression: [Arg] (co-repressor) high, binds to repressor, binds to operator region, block the Arg synthesis operon.
    • induction: [lactose] (inducer) high, binds to repressor, comes off operator, polymerase proceeds, lac operon is turned on
  3. positive control
    when something binds, gene expression is turn on {all about activator}
  4. eg of positive control
    • Maltose operon: [maltose] (inducer) high, binds to activator, which binds to activator binding site,
    • Lac operon: [cAMP] is high (when glucose is low), binds to CAP (catabolite activator protein), which binds to CAP binding site
    • Both binding promote the binding of polymerase with promoter region (weak promoter) and expression of the operon
  5. How to study changes in gene expression
    • Northern blot: one gene at a time
    • DNA microarrays: many genes at once; qualitative
    • RNA seq: quantitative; hard to interpret
Card Set
Microbiology - 0330 - Gene regulation
Microbiology - 0330 - Gene regulation