IPiB Thesis Defense June 4, 2024: Christine Hustmyer

Christine HustmyerChristine Hustmyer, an IPiB graduate student, will be defending her Ph.D. research on June 4, 2024. Her research in the Landick Lab focused on the roles the bacterial chromatin protein H-NS plays in gene silencing.

Hustmyer describes bacterial chromatin proteins as architects building structures for different purposes along DNA’s molecular highway. Her role as a scientist is to identify the purposes of these structures. Hustmyer’s research investigated the role of large filaments that H-NS proteins build along E. coli DNA, and how the filaments influence cell behavior.

Much of Hustmyer’s research focused on a strain of bacteria responsible for urinary tract infections in humans, which can become fatal if the bacterial infection is able to spread to the kidneys and into the bloodstream. She found that H-NS proteins create filaments along certain genes, blocking RNA polymerase from transcribing those genes. Some of the impacted genes encode for cellular behaviors such as toxin secretion needed for the bacteria to infect and persist in the human body.

“We found that the bacteria are already silencing genes in a way that prevents infection,” explains Hustmyer. “So then we’re left asking, how do the bacteria fine-tune this so that genes are either silenced or counter-silenced (the opposite of being silenced) to control virulence behaviors? How does the bacteria overcome silencing?” Hustmyer found when a protein called RfaH binds to the RNA polymerase, the polymerase can move through the H-NS filaments and continue transcription. This work is published in mBio. Additional work by Hustmyer has been published in iScience and is in press in Molecular Microbiology and Springer Nature.

Through her research projects, Hustmyer worked with and mentored undergraduate students. She found that the thrill of her own scientific discovery was just as exciting as guiding others towards their own discoveries. “There’s such a joy in seeing students develop skills and independence. The most important part of graduate school for me was learning that I love teaching and mentoring, and that these are services that I can provide for undergraduate students, just as they were provided to me when I was an undergrad,” says Hustmyer.

With a career in education and mentorship in mind, Hustmyer sought opportunities to build her teaching skills through opportunities across campus and in the Madison community. She further developed her tools for teaching and mentoring through the Delta Program in Research, Teaching, and Learning, which offers workshops, courses, and internship programs to build evidence-based teaching practices.

She overcame her fear of public speaking through her participation in the Chemistry-Biology Interface Training Program, which required that she give public presentations and participate in journal club presentations and discussions. She used the annual broader impact statements required of her NSF Graduate Research Fellowship funding to think about how to contextualize her research beyond the lab bench. Hustmyer, who served on IPiB’s Graduate Leadership & Development Committee as well as the DEI Committee, also worked on communicating scientific concepts quickly and clearly when she competed in the Graduate School’s Three Minute Thesis competition.

Throughout graduate school, Hustmyer volunteered at Madison’s Henry Vilas Zoo as a Wildlife Champion, where she communicated information about the animals supplied by zookeepers to visitors.  “When I moved here, I wanted to be involved in the Madison community. I just like volunteering for things because acts of service are really what fulfill me,” says Hustmyer. “It ended up being a useful exercise in thinking about how to communicate complex ideas, and that’s been one of the big things I have tried to work on throughout graduate school.”

As Hustmyer explored training in teaching and mentorship alongside her research, she had the support and guidance of her own mentors. “Bob has always been very supportive of me, including my need to spend time away from the lab to complete my Delta Program teaching internship at Madison College,” says Hustmyer. “He and each of my committee members had their own mentorship style that I learned from. And they’ve all given me really great advice regarding my research and my career.”

Hustmyer will continue to develop her teaching, mentorship, and research portfolios as a biological sciences lecturer at UW–Madison and a postdoctoral researcher in the Landick Lab before pursuing a career in teaching, mentoring, and research at a primarily undergraduate institution.

To learn more about Hustmyer’s research, attend her Ph.D. defense, “H-NS-mediated Mechanisms of Transcription Elongation Silencing and Counter-silencing in K-12 and Uropathogenic Escherichia coli” on Tuesday, June 4 at 1:30 p.m. CT in Room 1520 of the Microbial Sciences Building.