I find this one of the toughest questions to answer. I can think of an explanation fairly readily but it’s hard to know if I’m really giving an answer that means something to the person I’m talking to. I’ve often wished I could teleport the two of us to the lab to answer because I think it makes more sense if you can show someone – and that, of course, is one of the wonderful things about having a blog!
I look at the nervous system of fruit flies (Drosophila melanogaster) to try to understand how the nervous system is wired. The nervous system is basically a very complicated electrical circuit and if the wires aren’t in the right place to be connected up, the body can’t function properly.
This is a female fruit fly next to a penny
This is what the embryo inside looks like, magnified 100 times!
I then use different techniques to visualise the nervous sytsem of the embryo. In the picture below you can see the ventral nerve cord and developing brain lobes. The ventral nerve cord is the fly equivalent of our spinal cord, it doesn’t have a bone structure because they’re invertebrates and it’s on the ventral side, the front, rather than along the back. When the embryo hatches into a larva it’s head will be to the left and it’s belly at the bottom, so it’ll crawl ← that way!
Different antibodies bind to different proteins and this allows me to visualise different nerves. Staining the embryos with an antibody basically involves washing whole embryos in different clear fluids for different lengths of time!
This is the ventral nerve cord once I’ve dissected the embryo. Each bit of the ladder corresponds to a segment of the larva or maggot as one of the guys at work always says! The head of the embryo is on the left as above.
Here you can see the motor nerves. They connect the brain to the muscles and carry signals to each muscle to make it contract and allow the larva to crawl.
I think the patterns are really beautiful and it’s really amazing to be able to see each nerve. This is one of the reasons I work on fruit flies: Their nervous system is complicated enough that what we find out will be relevant for humans as well, but they’re simple enough that you can see what’s going on.
This is by no means all that I do but this is the central part of my research, how I get answers to questions such as ‘Is that gene involved in guiding nerves to their target?’ and ‘Do those two genes work together or do they affect different parts of the process?’. I look at when and where the gene is switched on and then what happens when I remove it or when I add extra copies.