Gene Team’s blog
By Latisha, Sarah, Travis, Miranda and Hilary
On our first day at GTAC we conducted an experiment, this was the Wiggle Assay (An algorithm that indicates the amount of movement made by a specimen), During The experiment we divided 200 Canton S. larvae into 8 wells with a Sucrose Solution and vice versa with 200 Da1ko (Drosophila Alpha 1 Knock Out) and timed at point 0 (Start of the Experiment), then we added Insecticide (Imidacloprid) to 4 of each different Well. We add the same amount of Sucrose to an Equal amount of wells and subtracted the same amount that we added because when we put the two solutions in they had mixed enough to take out the same quantity. After this we recorded each group of four wells every 15-30 minutes to keep track of activity in each well so we could use the data.
Day 2 began with an analysis of the data from the Wiggle Assay. Data from the Wiggle Assay Index was given to each group to interpret and normalise. We divided each time point by the starting of zero to compare the wiggle movement after the insecticide was added. We developed graphs to represent the data in a clearer way.
The data of the resistance or susceptibility of insecticides on Canton S. Drosophila
After morning tea, Dr. Frazer Thorpe showed us the Electron Microscope. It fired electrons on Drosophila to create a detailed magnification. A vacuum was created so that the electrons could travel without resistance from air particles. The specimen was placed gently onto a carbon sticker that was stuck to a stage about 1cm in diameter. A carbon sticker was used because carbon absorbs electrons which means the specimen was able to be distinguished from the stage. The microscope created an image that magnified up to x20000 and it magnifies to cellular level. Under the microscope, we magnified a Wild Type Drosophila, a Tm3/Tm6 Drosophila (with curly wings) and we looked at images of a Drosophila that had had a gene deleted that caused normal wing development.
In the afternoon, we went to the Doherty Laboratory to look at different species of Drosophila under a Light Microscope. All of the specimen were compared to the Wild Type Drosophila based on their phenotypes. Tom explained about dominant and recessive genes in a species and patterns of inheritance using punnet squares.
Unlike the other days, day three was consistently practical. The practical we worked on was extracting genomic DNA from two different Drosophila’s; the wild type and the mutant fly - that was hypothesised to have a segment of DNA called the Ban-Jheh element. During the course of the day we extracted DNA from the three samples of flies. We did this by using Lysis Buffer to help assist the cell membrane in the fly to break down. After doing this we washed the DNA in two column washes. When we were left with DNA we had to go into a PCR (PCR: polymerase chain reaction). This machine heats and cools down the DNA and it clones the DNA. Once we had made our Deoxyribonucleic acid DNA we tested it in a gel. The DNA ‘swam’ through the pores in the gel. The DNA samples vary in length depending on if it has mutant elements in it or jot. The samples that have shorter fragments in it- the mutants- travel further through the gel. Once the experiment was completed we analysed the samples and found out that one of the samples was a mutant; however the other samples were inconclusive.