An ode to the fruit fly

For someone who once wanted to translate science to the masses, I recently realized that I have done my own research a major disservice. I tend to discuss what I study instead of the subject I use to study it. To relate to the “lay” person, I convert my research into things that the average person can relate to. It’s not just for the lay person. These days, the people funding research want to know how your work is applicable to human disease and well-being. The unsaid stuff seems to be: if it’s not directly applicable, why are you doing it? So we learn to spin.

“Elucidating this thing will yield insights into depression and metabolism.”

It’s not that it is not true. It’s just that there are a million steps in between and that’s the way it should be.

Research is divided into subsections depending on stage of obvious usefulness to humans. There’s clinical research. This is when we study the effect of drugs or other interventions to human subjects. If you read something that refers to a “stage 1, 2, or 3 trial,” it means we’re doing stuff to humans. Before that is translational research. This is research done for the dedicated purpose of solving a human problem (without doing stuff to the humans yet). Basic research is translated into something that can be applied towards human biology. What’s basic research? Basic research is the individual block that allows us to build useful structures. This is where the soundbites of silly sounding research usually originates. I know, I know, why are we playing with worms? More importantly, why are we PAYING for people to do this? Well, the things is, without the blocks we can’t build anything.

Here’s a story:

In 1961 Osamu Shimomura was collecting jellyfish. Tens of thousands of jellyfish. Very simply, the purpose of his research was to figure out what made the jellyfish glow. He and his colleagues later identified green-fluorescent protein or GFP. If you’ve ever observed a pretty picture of a cell all lit up (regardless of color), you can thank this research. GFP and its derivatives are used in nearly every research laboratory around the world. It is used to show us where proteins or other molecules are located, even in live animals! Versions of it can also be used to tell us what cells are doing. You can imagine why these things would be helpful. At the time, even Shimomura couldn’t imagine the immense contribution GFP would be to the world. He, along with Martin Chalfie and Roger Tsien, was awarded the Nobel Prize in Chemistry in 2008.

My graduate research was on studying circadian behavior using the fruit fly as my research model. The fruit fly that pops up when you leave fruit out in the summer and dives into wine glasses has also helped make immense scientific discoveries. The fancy name for the kind I used is Drosophila melanogaster. The father of modern genetics is Thomas Hunt Morgan. Using the fruit fly, he discovered that heredity is dude to chromosomes (Nobel Prize in Physiology or Medicine, 1933). In my field, the first discoveries on how circadian rhythms work were also done with fruit flies (Nobel Prize in Physiology or Medicine, 2017). There are four additional Nobel Prizes for work involving fruit flies (1946, 1995, 2004 and 2011). So yeah, scientists are into fruit fly findings.

Why though? Look, I am not saying we’re the same as a fruit fly. They have about 100 thousand neurons. Humans are estimated to have about 100 billion. Here’s the thing, 100 billion neurons is extremely hard to study. Where I, the human, might have four versions of a single protein that is hard at work involved in 50 different things. The fruit fly might only have one version. Four is greater than one. One is easier to study. You can change one and try to figure out what the consequence is. If you change one in a mammal, maybe the other three pick up some slack. Good backup system but not helpful if you’re trying to figure out why it’s there in the first place.

There are fruit flies in each of these tubes.

Imagine our different model systems as different gaming consoles. They all have benefits and drawbacks. Lets say the fruit fly is the Playstation 3 and the mouse is the Nintendo Wii. I played fun games on my Wii (Just Dance!) but spent far more time on my Playstation because there were hundreds of games to choose from. This is how I feel about the fruit fly. There are tools to allow us to easily manipulate specific genes in specific cell types at specific times. That’s a lot of control! Yeah, you can also do that in a mouse but it sure isn’t easy or quick. Why? Flies have four pairs of chromosomes. Mice have have 20 (humans have 23). It’s definitely more straightforward to manipulate four of something in comparison to 20.

Extremely simplified protocol comparison:

If I want to find out where something is located, I take flies that contain the directions and flies that produce the color and have them mate. Roughly 10 days later, I’ll have children flies (lots) that glow where the thing is located. I can then take out the brain, look at it under a microscope and take pretty pictures with my answer. With mice, it take weeks to get offspring (maybe around eight of them). You might have to do something called genotyping to figure out you have the right one. This involves collecting DNA, a bunch of reagents, a machine and then looking at bands on a gel. You then take out its brain, slice it up in thin sections since it’s too thick to see through, and then look at it under the microscope.

Gratuitous Picture of a Fly Brain Cell

Look, before you learn calculus, you should probably know some algebra. Before you attempt any James Joyce, you should learn to read. I’m not trying to hate on mice here. I just want to give some love to the fruit fly because it has given us a lot. I still get annoyed when they appear in my kitchen. I’m not a weirdo. It would just be cool if we could take a minute to appreciate the literal small things in life.

Learn more links:

The Golden Goose Awards are awarded to random and obscure sounding research that have resulted in important breakthroughs.

Osamu Shimomura’s Nobel Profile: “Immigrants, we get the job done!”

Circadian research gets respect! Also, my amazing graduate school mentor worked on some of this research so it’s my greatness lineage.

Technically a neuroscientist. Prone to rants.