If we under/overexpress glial genes associated with Alzheimer's Disease will memory be restored?

We have identified 10 candidate genes expressed in glial cells that play a role in Alzheimer's disease. We want to under or overexpress these genes depending on their expression level to see if Drosophila with Alzheimer's memories can be restored. Using this simple model, we hope to gain a better understanding of the genetic makeup of Alzheimer's Disease in hopes of getting one step closer to a possible treatment. 

Prior to training for the memory tests and before we ordered our stocks, we wanted to make sure two sweet odors were balanced (the flies showing no preference for either). However, we were unable to balance the odors in the Y-maze and will be switching to a T-maze in Spring 2022. The picture to the right depicts the first step in odor balancing, which was to dilute the concentrations of octan-3-ol and 4-methyl cyclohexanol. 

1. Odor Balancing

   1. Tear off filter paper (about the size of a quarter) and label each OCT or MCH. Pipette 20 microliters of each onto the filter papers. 

   2. Place filter papers inside the Y maze vials, tap down to get the paper at or near the bottom. 

   3. Place vials onto Y maze. 

   4. Transfer untrained flies that were starved for 24 hours to small cup of Y maze

   5. Place cup into Y maze. 

   6. Let flies make choice, count numbers 24 hours later

We set up two crosses:

1. Canton-males X vglutGal4-female virgins

2. vglutGal4-female virgins X UA-AB42-males

We had issues balancing the two sweet odors in the Y-maze. It appeared the flies had a preference for one odor in one trial, but would prefer the other odor in the next trial. What we wanted to see was no preference for either odor so we could pair one of the odors with sucrose for our memory tests. 

We concluded that we need to switch things up for next semester. We gave the Y-maze a thorough effort, but realized we need to try something different. At first, we were dismayed; however, we realized that these things happen in laboratory experiments. It is very rare for an experimental protocol to work the first time. Even though the experiment did not work when balancing the odors, we gained ample experience in serial dilutions, transferring flies, using carbon dioxide to anesthetize the flies to count them and look for phenotypes, and observing all the genetic mutations (such as curly wings, stubbled bristles, and fewer bristles). 

Due to complications with the 3D printed Y maze and an inability to balance the odors, we are going to focus on working with a T-maze in the Spring 2022 semester. With a T-maze cut from plexiglass, we are hoping to balance the odors and train the flies and test our 10 candidate genes.