Cassie Joiner

Cassie Joiner was born in Portugal and raised in Dearborn, Mich. Her college career started at Madonna University in Livonia, where she studied chemistry and minored in biology. She’s currently a fourth-year graduate student working in the lab of Professor Anna Mapp at the U-M Life Sciences Institute.

“What I appreciate the most about LSI is how collaborative and connected everyone is — the spacious laboratories help create a strong environment for working together with several different labs,” she says.

What are you studying?

The Mapp lab is a chemical biology lab that focuses on the regulation of gene expression, and I use photo-activaible unnatural amino acids to study the many transcriptional protein-protein interactions required for a gene to be turned on.

For a gene to turn on, there are more than 60 interactions that have to happen between an activator and all of the different transcriptional complexes. Not all of those interactions are known, and there is a lot of controversy over which subunits within these complexes directly interact with the activators.

So, my research focuses on trying to develop better photo-activaible unnatural amino acids — they’re not part of the 20 we all have in our bodies — that can help capture those interactions so that we can get a better picture of what’s going on.

Once you put the unnatural into a protein and irradiate the cell with UV light, it will create a covalent bond between the protein you put it in and the protein it interacts with. This process helps us capture interactions that are normally too weak or too fast for us to look at otherwise.

What would you want a general audience to understand about your research?

Our research in the Mapp lab is considered basic research. We’re trying to gain a better understanding of a very complex system.

I know most people want to hear about drugs and how science is going to solve a devastating disease — but our lab is focused on first understanding small pieces of the larger puzzle so that we can then piece together exactly what is happening when a gene is turned on or off.

We want to answer the smaller questions that open the doors to the bigger picture. And we want to know this piece of the system backwards, frontwards, left, and right— before we start trying to solve a problem at the disease level.

So right now, we’re trying to get a snapshot of what’s happening inside of a cell — I’m using a yeast model system— when the yeast are stressed different genes are getting turned on or off. That might sound simple, but we still don’t know how it’s all being orchestrated. Just getting a picture of exactly what’s happening with all of the interactions that are involved would be a big step forward.

 

— Interview by Christopher Ransburg