Making the Connections
2009 Distinguished Professor Peter Jung merges physics and biology to paint a picture of the fundamental mechanisms behind human disease
June 15, 2010
It makes flowers bloom and hearts beat. In fact, it's a universal physiological process shared by all life forms.
That’s why Peter Jung, Ohio University’s 2009 Distinguished Professor, is passionate about calcium signaling. Unlock the secrets behind this and other molecular mechanisms, and scientists not only will understand this basic function in nature, but potentially could apply that knowledge to understanding many human diseases and pathological conditions.
Jung, for his part, is attracted to answering fundamental questions. “I don’t have the ultimate answer or holy grail—I’m not trying to understand how life came about,” he says. “To me, a good scientific problem to work on is everything. I just like to know how stuff works.”
Jung, who grew up in a small town in Germany, became interested in science around age 12, when he got a small kit with which to build radios and electric motors. He constructed other devices using scavenged electronic parts. “It was something fun to do,” he recalls.
Photo Credit: Kevin Riddell
Jung’s specialty is biophysics, which is what makes his approach to finding out “how stuff works” different. In this highly interdisciplinary field, scientists try to understand the physical mechanisms underlying biologic systems. Physics provides a framework that can be used to study anything material, living or non-living, from climate change and musical compositions to the patterns of brain waves during an epileptic seizure.
Understanding how the structure and shape of things relate to biological function is Jung’s main area of interest. His recent work focuses on two distinct processes: calcium signaling and axonal transport. “I’m interested in how the different parts of the system interact and regulate each other as part of an overall system,” he says.
In one line of research, Jung and colleagues examine how ion channels, which communicate information in the cell, impact calcium signaling. The scientists study this issue in astrocytes, a type of brain cell, and egg cells, which emit the massive calcium signal upon fertilization that starts life.
The team has discovered, for example, that certain arrangements of ion channels lead to different types of calcium signals, and that, in addition, the channels must be clustered together for certain biological processes to occur.
Unlocking the relationship between form and function also drives another important line of work for Jung and his colleagues, who are exploring how the structure of neuronal axons— which come in an incredible variety of shapes and sizes—affects the conduction of electrochemical signals. The size and shape of the axons, which make up the nerves in our bodies, are delicately regulated to conduct the signals from the nucleus to the next neuron. But scientists don’t yet know how this regulation occurs.
To solve the mystery, researchers are looking at neurofilaments, which determine the thickness of the axon. When the neurofilaments move fast, the axon is thin. If they slow down, the axon becomes fat. If the neurofilaments slow down too much, however, they can stop moving and accumulate in a “log jam.” The axon swells and stops working, which is the root cause of ailments such as Lou Gehrig’s disease.
Discovering these pauses in activity was a big surprise, because no one had even suspected that it was a possibility, says Anthony Brown, an Ohio State University biologist and former Ohio University researcher who collaborates with Jung on the work. “The discovery came as the result of computer modeling to simulate the movement of the neurofilaments, which led to the speculation that there were long periods of inactivity,” Brown explains. “Subsequent experiments showed that such periods of inactivity did indeed exist.”
The discovery is important because it can help other scientists understand how and why neurofilaments accumulate and lead to human disease. The team’s success reflects the benefits of interdisciplinary research and education. Because there is great demand for scientists who can think about biology and other subjects with computational skills, Jung co-founded Ohio University’s Quantitative Biology Institute, a research institute that fosters such interdisciplinary work among biologists, physicists, and mathematicians.
“In the future there won’t be a physicist and a biologist working on a problem,” he says, “there will be a group of scientists with different backgrounds working to solve a problem.” Regarding his own achievements, however, Jung remains modest.
“There are lots of people doing excellent work here at Ohio University. I was just lucky. I picked good problems to study. I think a key to success is to think out of the box and take risks versus following current trends. When I arrived at Ohio University, I was advised by colleagues that ‘you cannot work with biologists.’ Well,” Jung says with a mischievous grin, “I did.”
By Wenda Williamson
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