12. Eukaryotic Gene Regulation

Question 1

What Gal1 repressors bind to the Mig1 site?

Answer 1

Mig 1 binds to the Mig 1 site, which then recruits Tup1 to suppress Gal1

Question 2

What the the methodologic approach to realzing that there needed to be an activating domain (region) and a DNA binding region of an activator?

Answer 2

In summary, you can use either Gal4 or LexA activator binding domains to bind to the corresponding DNA binding site. The activating region, domain, of the protein can be eliminated which shows no activation or transcription of the lacZ gene.

But when the activating region is present, there is activation of lacZ gene. The activating regions can even be swapped, and the hybrid activators will activate from their DNA binding sites as normal.

Question 3

What is the most common bacterial regulator binding motif?

Answer 3

Helix-turn-helix

Most bacterial regulators are dimers with two-fold symmetry, and helix-turn-helix(HTH) motifs, one recognition helix and one helix contacting the backbone.

Question 4

Name 4 different eukaryotic regulator recognition helixes?

Answer 4

Zinc Finger Domain

The Leucine Zipper

Helix-Loop-Helix

and I think they include the Helix-Turn-Helix