Author Archives: Melissa White

The End of the Road

Before my journey at Duke began, I never thought I would do research. I saw research as just working with mice 24/7 and doing menial tasks, not anything special at all that I would enjoy. And yet, something in my head told me to try it anyway. I thought, I go to Duke, a university with so many opportunities to cash in on. What kind of student would I be if I didn’t do exactly that, and see if research really was all that I expected it to be? And next thing you know, I became apart of BSURF for the summer.

For one, research was not what I expected. First, I worked with flies and not mice (which was great because I still have yet to get over my slight fear of mice). Secondly, the tasks I did were in fact meaningful and were always important to my overall project or someone else’s. Also, everyone in my lab was welcoming and easy to speak to, which created a fun environment for me to make myself at home in the lab.

I learned a lot about myself and what I like and dislike about science. For example, while I do think the research I’ve done is interesting and will make an impact on humans someday, I realized that I do still love neuroimmunology and I think I would enjoy research that was more medicine related. Additionally, I want the research I do to directly affect patient lives in relatively short time spans (not sure what that really entails yet).

But overall, what I will take away from BSURF is that it’s okay to not know. In the beginning of this program I hoped that by the end I would have an answer as to whether I want to pursue research as a career alongside becoming a doctor. And now that I am at the end, I still don’t have an answer. However, by hearing from various faculty speakers, especially doctors that have been in my position, I realized that I just have to roll with the punches of life and take everything one step at a time. I’ve accepted that I won’t figure everything out now, and maybe with more experience  with research, my path in life will become more clear.

All in all, I appreciate the summer I’ve had. Although I have  more questions that answers, I don’t regret my decision to participate in BSURF and I’m glad I got to be surrounded by great scientists all summer.

A big thank you to Dr. Grunwald, Jason, my lab (especially Dr. Volkan, Bryson, and Ambika), and my fellow BSURFers for making this summer a great one! Thank you to Trinity College for funding my research. And of course, thank you to everyone that has taken the time to read my blog posts. 🙂

Much Needed Guidance from Dr. Lefkowitz

One of the things I look forward to the most each week are the faculty talks. I always find it valuable to be able to look into the life of a researcher and hear about their journey through life, especially since I don’t really know if I should take a path similar to theirs. They have all been great, but I think the faculty talk that stood out to me the most was Dr. Robert Lefkowitz’s.

Dr. Lefkowitz, unlike other faculty speakers, right off the bat said he wouldn’t be talking much about his own research, but of his life. That immediately stood out to me. During all of BSURF I have been going back and forth over if I really want to pursue research as a career, and I’ve been looking all over for guidance and advice. Somehow, I knew at that moment that Dr. Lefkowitz would give some to me.

As Dr. Lefkowitz spoke to us, I found myself seeing parallels between him and I. At first, he didn’t even like research and was very sure that he would become a doctor. I can admit that that was my mindset all throughout my freshman year and before I applied to this program. He ended up doing research so he wouldn’t have to serve in the Vietnam War (which is probably something I would do in his shoes too, to be honest) and still wasn’t very fond of research. And yet, after he left he found himself missing research and being in a lab.

My summer doing research has been one I can’t forget. And I think that I will find myself like Dr. Lefkowitz — missing research and wanting to come back. His talk opened my eyes to the fact that it won’t all be great at first. The research you do won’t always be successful. You’re not always going to know what you want to do and sometimes you will think you have your life all figured out, and then it takes a different turn than you expected. Who knows, maybe I’ll only become a doctor, or maybe I’ll be a doctor and do research. The thought of not knowing which path will be mine scares me. But Dr. Lefkowitz’s talk helped me to learn and accept that fact, and it’ll be one of the major things I take out of being apart of BSURF.

How does sensory experience mediate FruitlessM and DoublesexM expression in the fly brain?

In Drosophila melanogaster, the genes Fruitless (Fru) and Doublesex  (Dsx) control sex specific sexual behavior and experience-dependent sexual behavior, respectively. Additionally, mutants of the male form of Fruitless (FruM) and flies in isolation show a lapse in sexual behavior, indicating that experience has effects on courtship behavior. However, it is unknown how experience modulates the expression of these genes, and how this modulation effects future decision making and behavior in flies. Therefore, we asked how does sensory experience mediate FruitlessM and DoublesexM expression in the brain? To answer this, we placed flies in either a group housed environment or social isolation for five days and then dissected their heads. Chromatin immunoprecipitation (ChIP) and later ChIP-qPCR were performed to examine gene regulatory differences and endogenous enrichment, respectively, in RNA Polymerase II and H3K27ac. Our data suggests that with social isolation, the transcription of FruM and DsxM decreases, specifically in Fru and Dsx connected circuits. We believe this effect is circuit specific because enrichment in controls, Choline acetyl transferase (+) and Gustatory receptor 5a (-), are insignificant. Thus, our data suggests that sensory experience plays a role in future sexual behavior in flies and may contribute to neuroplasticity in the fly brain.

Collections, Dissections, ChIP, Analysis, Repeat

Like I have mentioned in my previous blog posts, my experiment is based around seeing what genes effect sexual behavior in the brains of flies. Depending on what gene (fruitless, doublesex 1 or 2, or ChAT) and what epigenetic marker (H3K27ac) or a proxy of transcription (RNA Polymerase II) we are focusing on, my day in the lab may be different.

For example, if we are just starting to look at one of the genes and epigenetic markers listed above, I will either collect adult male flies in groups of 30 or isolate fly pupa into their own bottles (1 pupa to one bottle). These collections set up group housed or isolated flies for my experiment.

Those flies are kept in their environments for about 5 days, so across that span I can collect more flies or start dissecting flies from previous collections. For dissections, I take the head off of the body of the fly and remove the mouth.

After dissections, ChIP protocol is followed to isolate the DNA that is related to the epigenetic marker we’re looking at. Following ChIP, we use computer analysis to quantify the enrichment of the respective protein or mark that the flies received from their respective environments at the promoters for each respective gene of interest.

This cycle is essentially repeated over and over again, so whatever stage of the cycle I am at is what I do during a day at lab. If I had to choose, collecting and dissections are my favorite parts!

We Love Sea Urchins

This week, everyone presented their chalk talks about their projects. It was fun and interesting to see what everyone was working on! I liked that a lot of the same areas of interest and methods (e.g. epigenetics, use of gRNA, mice etc.) could be seen across projects. But even then, there were still key differences among projects and I could clearly see the contributions they would make to science.

With that being said, I was particularly interested in Michael’s chalk talk titled “To Transfate or not to Transfate: Recognition of Skeletal Cell Presence”, specifically in sea urchins. My lab and I would always walk past the sea urchin lab and think about how cool it would be to work with them, so I was excited when Michael started to present.

Michael’s project looks at PMCs (primary mesenchyme cells) in sea urchins, which become the skeleton of  the sea urchin later in development. However, a previous study found that the skeleton still forms without PMCs because of NSMs (non-skeletogenic mesoderm). This led Michael’s project to focus on how the sea urchin embryo knows that the PMCs are missing and what signals are given after this is determined. He will determine the PMC genes, clone these genes through PCR, and look at them using in situ hybridization (ISH). He will also determine the signaling molecules through ISH as well as using drug treatments. Michael’s project is important to science because his project results are important for just general knowledge about the skeletal system, and could potentially be used to help skeletal diseases in humans in the future.

There’s a Lot to Learn, and from Many Different Avenues

Dr. Volkan is originally from Ankara, Turkey and grew up in Istanbul, Turkey. While living in Turkey she received her Bachelor’s and Masters degrees in Molecular Biology and Genetics, and then came to the United States to complete her Ph.D. in Biology at the University of Chapel Hill. Dr. Volkan then went to Los Angeles for 6 years where she did her postdoctoral research at the University of California Los Angeles, and some time afterward found her way to Duke where she is the Principle Investigator of her own lab.

At UCLA, Dr. Volkan wanted to find genes that regulated circuit assembly and gave structural properties to circuits. For example, where is a certain cell body for a cell going to be and where is it going to connect to in the brain? She ended up finding one mutation that shifted her focus from not only the development of the nervous system but also the evolution of the nervous system.

This observation led Dr. Volkan to the question, how is a complex nervous system built? She knew that as well as genes laying one replicable foundation, experience played a key role in how the nervous system is assembled and experience changes the brain, or makes the brain plastic. Therefore, she wanted to explore how experience and the brain are connected and this idea is the basis of what her lab explores today through the unique and powerful system of the Drosophila melanogaster.

Besides working in her lab, Dr. Volkan loves to teach and has been teaching since about 2010. She was a teacher’s assistant at UNC and teaches mostly undergraduate and graduate classes at Duke. She prefers to do a lot of team-based learning and active learning. Currently, she teaches a lab course in the fall and teaches the course Neuroscience 223, “Cellular and Molecular Neurobiology” in the Spring with another professor at Duke.

What I found really interesting about Dr. Volkan was that she was very interested in film, and took a lot of movie critique classes during her academic career. She liked to work with documentaries and independent movies. Dr. Volkan even had a job offer in the film industry, but instead, she decided to continue on with her graduate education! However, throughout all of this she was always been pro-science and knew that she always wanted to be a researcher, despite the fact that she never knew she would be managing a mini-business as she took control of her own lab.

As much as Dr. Volkan loves science, she feels like there are things that can change. She expressed that scientists need to be more open minded and more willing to take a chance on things that can be important or interesting. She says, “Science these days has become like a recipe” and sometimes scientists are too critical to the point where they don’t allow new things to be discovered. Consequently, Dr. Volkan finds herself expanding her interests and learning new things as she goes along in her science journey. She says, “The more [I] learn, the more [science] becomes more interesting”.

Dr. Volkan wants future researchers to know that it is not only a research job, but also has a lot to do with business administration. She says, “You should be very open to learning new things … things are going to change and you have to keep up with that change.”

She ends our conversation with the advice to “Always look for analogies in other systems … there’s a lot of things each science can learn from one another.”

Pelin C. Volkan, Ph.D. (Picture courtesy of https://sites.duke.edu/volkanlab/people/)

The Wonders of Sexual/Courtship Behavior in Flies

In Dr. Volkan’s lab, the primary focus of my project is to look at the genes that underlie the neural circuits that deal with sexual behavior in flies, specifically in Drosophila melanogaster. We already know about a gene named Fruitless or Fru in males that controls all male courtship behavior, and another gene named Doublesex that controls experience-dependent sexual behavior. In other words, the level of courtship these flies maintain controls whether or not doublesex is expressed. Additionaly, ChAT (choline acetyltransferase), a gene that encodes an enzyme to make the neurotransmitter acetylcholine, is known to be involved in the neural circuits that deal with courtship behavior. If ChAT is being used, then that means that neural circuits are being used as well.

Furthermore, in my project we are putting male flies (some with mutations in the genes previously mentioned) in different social environments where they are either group housed or isolated and look at the expression of those different genes. Studies have shown that group housed male flies that are mutant for Fru do in fact court one another and form a chain link (Villella et al.), while isolated male flies, when rejoined with other flies after isolation, fail to court alltogether most times (Pan and Baker). Consequently, if we separate male flies by their social experience, we can see what genes are turned on and off by protein markers such as RNA polymerase, H3K27ac (a histone epitope that deals with acetylation and is associated with the higher activation of transcription) and others.

In my project, we are using a method named ChIP, which is “a type of immunoprecipitation experimental technique used to investigate the interaction between proteins and DNA in the cell”. In this method, antibodies made specifically for proteins like RNA polymerase will attach to the proteins, which are also attached to genes, and will be taken out of solution by magnetic beads so that the RNA can be isolated and sequenced into DNA, giving us the DNA sequence related to the behavior we witnessed!

Overall, with this project our lab hopes to find out what genes in the brain let the fly know when to mate and who to mate with, or simply how the fly makes decisions when presented with a mate. This information will give us more insight on the circuit for sexual behavior in flies and can even be used to understand the human brain in the future!

Photo by Melissa White

Heads of the flies!

Photo by Melissa White

More fly heads because practice makes perfect!

Week 1 – To Be or Not to Be

One of the most important things I want to get out of my summer in BSURF is knowing if I want to continue doing research as I continue on in my undergraduate career and professional career. First of all, do I even like to be in a lab and do research? My experience in a lab has been limited to labs required for STEM classes, which have only introduced me to a small portion of science. I feel like I have been missing out on other areas of science because of my lack of experience. So, I want to use my experience this summer to gauge whether or not research is something for me.

I also expect to learn what other interests I have in science. For example, I am working in Dr. Volkan’s lab, mainly dealing with fly epigenetics and what genes underly the neural circuits of sexual/mating behavior. From research I have done over the years, I have been more interested in neuroimmunology, but I want to see if the subjects I am studying in lab are of interest to me to and are something I should explore in the future. I don’t want to end up limiting myself to a certain subject and then realizing later on that I am more interested in something else. I want to explore everything (or at least most things) so that I can be secure in my interests.

Lastly, I expect to learn. Whether it is learning about the things I’ve mentioned above, or even learning about myself, my personality, and my strengths and weaknesses. Everything is a learning experience and I want to do a lot of it as I go through this program. No matter what happens this summer I want to leave it with no regrets and with more knowledge than I entered with. I can’t wait to see what this summer holds for me and most importantly, what I do during my research experience!