LIFESCI 3 Lecture Notes - Lecture 24: Flac, Dna-Binding Domain, Tryptophan
Document Summary
Haploid/diploid analysis: oc = o-, acts on cis (locally on the same dna molecule) I- acts on trans: f"la(cid:272) = plas(cid:373)id, 1st row: wild-type - beta-gal only expressed when inducer present, 2nd & 3rd row: mutations in repressor & operon -> beta-gal transcribed regardless of inducer presence. 4th & 5th row: presence of plasmid, where lac z is mutated. 4th: mutant lac repressor (i); thru addition of plasmid with normal lac i, protein product diffuse into cell & bind operator sequence on mutant -> restore beta-gal activity. Allolactose isomerized from lactose binds lac repressor lac repressor comes off of operator. Only removes negative regulation -> low/basal level of beta-gal expression. Negative regulation on when no lactose present: activator binding site upstream to promoter. Positive regulation on when no glucose present. Cap has dna binding domain & activation domain (interacts with tail) Summary high glucose: high lactose camp low. Basal repressor unbound low glucose: high lactose.
