Homework SourseA positive result for the yeast twohybrid analysis means tha
A positive result for the yeast two-hybrid analysis means that:
| A) two fusion proteins interact with each other and because the Gal4p binding site domain on one fusion protein binds to the reporter gene and the Gal4p activation domain of the other fusion protein interacts with RNA polymerase, the reporter gene is activated. | |
| B) two fusion proteins, one containing the Gal4p binding site domain and one containing the Gal4p activation domain, have interacted through their Gal4p domains resulting in transcription of the reporter gene. | |
| C) the colonies growing are expressing the two fusion proteins and the two proteins have functioned independently. | |
| D) two fusion proteins interact with each other and because of the Gal4p binding site domain and the Gal4p activation domain contained in each fusion protein, the reporter genes are activated and the cells die, resulting in no colonies. | |
| E) two fusion proteins, one containing the Gal4p binding site domain and one containing the Gal4p activation domain, have bound together, which disrupts the ability of the reporter gene to make a blue colony. |
Solution
Answer: Option A
Protein X (bait) was fused to GAL4 containing the DBD (GAL4DBD) while protein Y (prey) was fused to Gal4 that contains the AD (GAL4AD). Expression of both fusion proteins and interaction between bait and prey reconstituted a functional Gal4 transcription factor. Gal4 then recruited RNA polymerase II, leading to transcription of a GAL1-lacZ fusion gene thus activating reporter gene.
