LESLIE KOYAMA
The Biology of Fruit Fly Intestines
Our intestines are one of the most incredible organs. Not only do intestines help us digest our food and take up nutrients to keep our body fueled, but they also protect us.
How do they protect us? Even though our intestines are inside our body, they are constantly interacting with the outside world through the food we eat. So just like our skin protects us from the outside world, our intestine protects us from anything harmful in the food we eat.
I study the intestine in the humble fruit fly (Drosophila melanogaster). The fruit fly has been studied for over 100 years as a model organism because they are cheap and easy to maintain, produce many offspring to study, and live short lives.
View from the microscope. Left: Fruit flies under a dissection scope, knocked out using carbon dioxide. Right: A fruit fly intestine. I fed the flies blue food dye to stain the inside of the intestine blue. The fruit fly intestine is about the size of an eyelash.
Despite their small size, fruit flies can be incredibly beautiful. In this microscope image, each blue dot is a single cell. From here, you can already see that the blue dots cluster together in unique ways, the different clusters of blue dots are actually unique organs within the abdomen (or belly) of the fly. How many different organs do you think you see?
The fiery white/orange webs that sprawl across the abdomen are not neurons as you might think. They are actually the trachea which is a system of branched tubes that the fly uses to breathe. If you look closely, the thick branches end in five distinct, black circles. These circles are the spiracles, or the holes through which the fly breathes. Unlike humans, flies breath through their sides instead of their mouths! Wild!
If you want to learn more about this image and see other images like it, feel free to read the paper I published on the technique that made this image possible. Link.
Why flies? And how?
How does one even work with flies? To learn more about all things fly, check out this wonderful video that my good friend Alex Dainis made of me talking about my work.