AMES, Iowa - Laboratory work in many undergraduate classes is focused on achieving a certain outcome. For Wren Murzyn, a senior in genetics at Iowa State University, uncertainty in the lab has been more valuable.
As a freshman in fall 2022, Murzyn enrolled in Biology 1140X, a one-credit course designed to give first- and second-year students hands-on research experience. Her section was taught by two faculty members in genetics, development and cell biology, adjunct assistant professor Ping Kang and associate professor Hua Bai. That led to working in Kang’s lab the next four semesters, contributing to research exploring the genetic causes of aging in fruit flies.
“When you’re in an actual research lab setting, you’re encouraged to make mistakes and learn from them,” Murzyn said. “Pushing forward, repeating experiments and refining techniques are all part of the process. The more effort and repetition you invest, the more you learn and improve, and the more rewarding the results become.”
The results were especially rewarding when Murzyn was credited as a co-author of a recent research article published in Proceedings of the National Academy of Sciences. The study described how researchers found that fruit flies missing a crucial developmental hormone, PTTH, enter the pupal stage about a day later than usual and subsequently end up living up to 30% longer. The flies’ elongated lives were marked by reduced inflammaging, the chronic inflammation associated with aging.
“Their increase in inflammation is much slower as they age,” said Kang, the paper’s lead author. “It’s a robust difference. Every time we repeated it, they lived longer.”
Comparing RNA expression of standard fruit flies and no-PTTH flies connected the reduced adult inflammation in the longer-living mutants to a signaling pathway, NF-kB, that plays a crucial role in the immune responses animals use to fend off pathogens. Gene knockout experiments showed that the enhanced longevity only came when NF-kB was silenced during the larva-to-adult transition and within the flies’ liver-like oenocyte cells.
The study could help scientists potentially lengthen human lives. While there is no directly comparable growth hormone to PTTH in mammals, other hormones could have a similar effect via immunity signaling, Bai said.
“If we understand the fundamental mechanism, it may be possible to manipulate it,” he said.
Murzyn’s role in the study was developing a protocol for peeling off a fly’s pupa case to dissect the oenocyte tissue, a method established via trial and error, consistent practice, careful observation and detailed note-taking. Five other undergraduates were fellow co-authors for their efforts measuring fly lifespans, meaning Iowa State undergraduates accounted for one-third of the paper’s 18 authors.
Working with fruit flies is an ideal fit for undergraduate researchers because the flies are inexpensive, easy to handle and short-lived, Kang said.
“Most students are so intimidated at first. They don’t want to screw up. But I always tell them don’t worry, we’ll start over if they die,” she said.
Murzyn is from Fort Collins, Colorado, and chose Iowa State in part due to the support available for women in STEM fields. But her research lab experience allowed her to immerse herself in scientific discovery more than she dreamed possible. It solidified her plan to attend graduate school after graduating in fall 2025, with hopes of pursuing a career studying the genetic underpinnings of human diseases. She’s fascinated by the field’s vast potential, the uncertainty around every corner.
“I like that there’s always more to discover. There are limitless possibilities,” Murzyn said.
Contact
Ping Kang, Genetics, Development and Cell Biology, pkang@iastate.edu, 515-294-9395
Hua Bai, Genetics, Development and Cell Biology, hbai@iastate.edu, 515-294-9395
Dave Roepke, News Service, dcroepke@iastate.edu, 515-294-4845