Thinking Thoughts: Rotations

Hey, sorry I’ve been MIA for a little while. I’ve started my third (and final, unless something really unfortunate happens) rotation and have had a lot of thoughts about what I enjoy about research and what I need in a PI/mentor/boss/lab environment, exactly none of which I have been able to put into a solid idea for a blog post.

Also rotations are sort of like the early stages of dating, except with a really pressing and Big Life Decision edge. You’re simultaneously trying to make sure you’re making the best impression (because there might be several students who all want to be in your favorite lab, and there’s only one spot), but you’re also trying to feel out whether the lab is what you’re looking for. This also involves a lot of gossip, which I find super awkward, but which is absolutely necessary. You have to ask people their least favorite things about the lab or the PI or the research. And that’s always an awkward thing to ask. Especially since I tend to make decisions based on the bad. I can pretty quickly figure out what I like, but figuring out potential problems (preferably before you’ve made a 5 year commitment) is harder in just 4 weeks.

And then you leave the rotation with a sort of, “This was great! Maybe I’ll see you almost every day for the next 5 years, or maybe not!” It’s doubly sad because I’ve really enjoyed hanging out with all of my labmates during rotations (other grad students, post docs, lab techs), and I’m worried that no matter which lab I join, I might end up very rarely seeing people in the other lab. Though I now do trivia every week with one lab, so that’s really great (and we actually won second place this week!!!). And while yes, the research and the PI are incredibly important in choosing a lab, the people you work with make some of the biggest impacts on day-to-day enjoyment and fulfillment. They’re the ones who will go get drinks with you [if you’re under 21, change that to soda/ice cream] when you have the inevitable setback. They’re the ones who will teach you how to do the new technique you’ve never done. They’re the ones who will motivate you to show up to lab when it’s -20 degrees out because you definitely have to talk to them about last night’s episode of whatever because it was AMAZING.

So today’s post has been very rambly, but those are at least 20% of my thoughts related to rotations recently.


Model Organisms: Worms, Flies, and Mice, Oh My!

The other weekend I volunteered at an Exploration Station at the Wisconsin Science Festival. Graduate students had booths set up where there were activities and demonstrations, targeted for younger children. I helped out at a booth called Build Your Own Fly where we told kids a little bit about fly phenotypes (phenotypes are characteristics, such as eye color or hair length), and then had an arts and crafts project where kids could make a fly with the features they wanted. Part of the point of the booth was also to teach kids about why we study fruit flies. And I was surprised that so many adults, let alone kids, didn’t know why we would study them.

So today’s post is on model organisms! Hopefully this will explain why so much research that is important to understanding how humans work is actually not done on humans at all.

People are very hard to study. Obviously it’s unethical to give people dangerous drugs or perform unnecessary major surgery on them. But we also can’t put them under the microscope, we can’t control what environment they developed or were raised in, and we can’t track them throughout their entire lifespan. If we tried to figure out how human biology works from only studying people, we’d never get anywhere.

That’s where model organisms come in. They’re animals or other living organisms that we can study and use to learn general principles (and even some amazingly specific details) that then apply to human biology as well. For instance in my last rotation, I studied frog spinal cord neurons under the microscope. And even though these neurons are from frogs and were dissected out and lived on a glass slide for a day, we can still use what we learn from them to make good guesses about what a neuron in a developing person would do. This is possible because of evolution. All living things have similarities because they evolved from some common organism. So even though people are very different from frogs or flies, we all have neurons. And those neurons all work pretty much the same ways. And they even have some very similar proteins. Proteins are basically the things in cells that do things; you can almost think of them as little robots that have a job and go around doing that specific job. So in my current rotation, I was studying microtubules, which are part of the cytoskeleton of the cell. Microtubules help give lots of cells their shape, but in neurons they also act as highways that proteins can ride along to get to a different part of the neuron.

You may have seen this gif before:

That walking protein (motor protein) can carry other proteins (and some other things, like that blue blob in the video) along the microtubule highway.

Well both people and flies have microtubules and motor proteins, and they’re very similar (in fact flies share about 60% of human genes). So we can do things like put glowing versions of microtubules and motor proteins in flies and observe them under the microscope, which we’d never be able to do with people.

And the same holds true for other model organisms, with different organisms having different advantages. For instance, if you wanted to study the skeleton, you would need to use a vertebrate. So fruit flies are out, but mice might be a good bet. But if you wanted to study neurons in a living embryo, mice can be really tricky. But flies or zebrafish or C. elegans might be a great choice instead, depending on what specifically you were studying.

And actually C. elegans (pictured below) are amazing for development and basic neural circuitry research because they are completely developmentally mapped. A few decades ago, someone sat down and tracked which cells divide into which ones so that we know exactly how many cells the adult has and which cells they came from in the younger worm. They also have only 302 neurons, which is so much easier to study than the approximately 4 million in mice and especially the 80 billion neurons in the human brain.

So biologists study lots of other organisms, and each of them are important and useful in their own right. And the most useful is for researchers to collectively study all of them. Because understanding the differences between different organisms can be as important as understanding what they have in common (for instance: why can salamanders regenerate limbs, but we can’t?).