Below you can find the data I collected from the offspring flies:

-> offspring from trained parents

-> offspring from untrained parents

(I left out data from flies that showed negative preference during two training periods in a row)

Since the results I got after training the parental flies looked a bit odd on first sight I decided to take a closer view…

First I excluded some weird animals that either showed a larger preference for one side than avoidance or showed no avoidance two training periods in a row:

Next I compared the behavior of flies that showed avoidance but no learning with the behavior of the remaining flies:

-> Avoidance is almost the same but note the first test period!

Lastly I split the data according to male and female flies. Here is what I got:

-> Looks a bit like there is negative learning in the male flies however I don´t have enough data to be sure…

As an overview here are all the flies (except for the excluded ones) together again:

Below you find the data from my experimental rounds A and B:

-> learning scores of the parental flies from experimental round A and B

-> learning scores of the trained parent´s offspring only from experimental round A

-> learning scores of the untrained parent´s offspring only from experimental round A

The results confuse me a lot and I am happy to discuss reasons :) However the offspring of the round-B will be ready for testing by the end of this week so there is still some data to collect…

DNA Assembly in a 1:2 ratio of vector to insert with gRNAs of rsh and rut (Q5 and template concentration: 640 pg/µl) and 100ng of pCFD6 BbsI AP (using QuickCIP). Heat-shock (hs) transformation into E. coli (DH5α competent) with 10 µl Assembly Reaction and 100 µl cells.

For Crtl, pCFD6 BbsI AP was wrongly used.

DNA Assembly in a 1:2 ratio of vector to insert with the gRNAs of rsh and rut (Q5 and template concentration: 640 pg/µl) and 100ng of pCFD6 BbsI AP (using FastAP and 2 extraction steps). Heat-shock (hs) transformation into E. coli (DH5α competent) with 10 µl Assembly Reaction and 100 µl cells.

For Crtl, pCFD6 BbsI AP was used in reaction.

The offspring of my first experimental fly cohort finally hatched! Below you find a few first pre-tests I ran last week :)

First, here are the results of a quick test to see if the offspring shows a preference for the parentally trained side after the first training period:

After that I played around with the laser a little bit to find the learning threshhold. I set the laser on 2,6V but the results I got look a bit weird:

-> untrained wtb flies

-> offspring of trained wtb flies

I´m optimistic however there is still a lot of work to do…

Via gDNA analysis and PCR was the specific area of the rsh gene extracted and amplified where the nucleotide substitution: C to T (Folkers et al., 2006) should be for the rsh¹ mutation. The amplicon was Sanger sequenced which proved the nucleotide substitution.

Hello everyone!

Things are not going well…

Over the last week I have encountered numerous problems in carrying out the planned experiment, and the biggest of these is definitely the generation of offspring. Since it has been shown that long-term memory decays quickly in the first 24 hours after operant self-learning on the flight simulator (and with that possible epigenetic marker I suppose), I decided to mate the flies immediately after training and separate them again after 16-20 hours. However, I did not get any offspring by doing this. I tried mating virgin males/virgin females and also adult males/virgin females for 16-20 h, but no eggs could be found in the vials. I have not yet found out what prevents the flies from mating and am now trying again with older (3-4 days old) adult male flies. 

Another problem is the training protocol for memory consolidation by S Xia, L Liu, C Feng et al. 1997. Although I have practiced gluing and inserting flies into the flight simulator, I don’t think I can train enough flies in one day. To maintain sufficient larval density after mating, I need at least 5 females and 2-3 males, and I would need to train them twice, giving a total of 16-18 training rounds per day (and that doesn’t include failed attempts…). Alternatively, I can use the standard protocol and see if the training is enough to reveal epigenetic inheritance of acquired habits, if any. 

For now, I will continue to try to produce offspring and practice gluing and training the flies. I have started to do further research on inheritance mechanisms to see if it might also be possible to work with only the F0 generation and detect epigenetic markers (methylation of genes, e.g. foxP, siRNAs) in the trained flies and compare them with untrained flies. Here (1, 2) you can find a few interesting articles on this topic.  

However there is also some good news to report: my ContonS line will be ready soon, so I don’t have to work with the wtb virgin flies anymore, which decease very quickly. I have also made some progress on the statistical background after talking to a friend of mine although I still need to do some research on how to set my effect size so I can finally calculate the sample size I need for the experiment.