Biophysical Society Bulletin | October 2024

Biophysicist in Profile

that exogenous molecules can be injected into the living cell. It was discovered in the 1980s that the cell membrane can be transiently permeabilized by using an intense electric pulse. Various types of molecules, including DNA, RNA, and proteins, can be introduced into living cells by using this method. How ever, it was not clear at first what the physical mechanism involved in this process is. Chang was an early investigator in this field and made major contributions in delineating the physical mechanism involved in electroporation. He explains, “In the 1990s, a powerful bio-photonic technique using green fluorescent protein (GFP) emerged. The gene of GFP can be edited and fused with targeted proteins and then expressed in a living cell. Using such fluorescently labeled molecules, it becomes possible to use optical methods to investigate the signaling pathways in vivo. By using genetic engineering methods, GFP can be modified to develop novel biosensors to rapidly screen new drugs for cancer or neuro degenerative diseases (such as Alzheimer’s disease).” Using a fluorescent probe and confocal laser microscopy, he was the first to demonstrate that a localized Ca 2+ signal is involved in regulating cell division in embryonic cells. This signal was absent in the domestic cells. “In collaboration with Professor Roger Y. Tsien of the University of California San Diego—2008 Nobel Laureate in Chemistry—I used GFP based bio-photonics to show that the mammalian cells use the Ca 2+ signal receptor (calmodulin), instead of the Ca 2+ ions, as the key signaling regulator for controlling the cytokinesis process,” Chang details.

He notes, “Biophysics is a truly interdisciplinary field. It covers a very wide area in the study of nature. So, there is a lot of room for innovative research. One is only limited by his or her own imagination. That is great! Also, biophysics is pretty down to earth. Unlike some other fancy studies such as parti cle physics or cosmology, the major hypotheses in biophysics usually can be tested in experiments.” Asked about where he thinks the field of biophysics will go in the future, Chang postulates, “I think in the future, biophys ics will continue to be a booming field. There will be many opportunities in this discipline. I foresee the need to use more quantum physics in this field. Most of the biophysics studies today use classical physics and traditional chemistry. This may not be enough. Living systems are built on atoms, molecules, and macromolecules; cellular structures are really nanostructures. Their operational principles should be under stood at a quantum physics level. Now, with the advancement of technology, we can do new modeling and have new under standings. That is also what I plan to work on. I will collabo rate with physicists, neuroscientists, and quantum chemists to contribute to this field.” In his free time, Chang serves as a BPS Ambassador repre senting China. Outside of science, he enjoys sports, reading history, and watching news. He played tennis regularly for many years and was also a table tennis champion during his time at Rice University.

Celebrate a Decade of Biophysics Week! Join us for a milestone event as we mark the 10th anniversary of Biophysics Week! This is not just any celebration—this is a chance to highlight the important research, contributions, and discoveries of those working in biophysics! Whether you’re a seasoned researcher, an aspiring student, or simply passionate about science, this is a great opportunity to get involved. Be part of history by hosting your own Affiliate Event during this extraordinary week. Don’t miss out—let’s make this Biophysics Week the most memorable yet! For more information, visit www.biophysics.org/outreach/biophysics-week/be-an-affiliate-event-organizer. #BiophysicsWeek

October 2024

7

THE NEWSLETTER OF THE BIOPHYSICAL SOCIETY