Voices of the College
Neuronal expression pattern of tomosyn, along with another synaptic marker (Bruchpilot) at the fly neuromuscular synapses. Image by Jacqueline Bonds
Janet Richmond and David Featherstone have determined that there is a link between the nerve signaling inhibitor tomosyn and long-term memory. Professors in the Department of Biological Sciences and faculty in UIC’s Laboratory of Integrative Neuroscience, the husband-and-wife team of Featherstone and Richmond have been studying the protein’s effect in the learning behavior of fruit flies, a function that requires many of the same proteins used in higher animals, including mammals. The study, “Tomosyn-dependent regulation of synaptic transmission is required for a late phase of associative odor memory,” was published in the October 31, 2011 online early edition of the Proceedings of the National Academy of Sciences.
Janet Richmond. Photo by Kathryn Marchetti
The research team found that tomosyn plays an important role in regulating the amount of neurotransmitter released at the synapse, the junction where messages are relayed between nerve cells. Tomosyn can limit this signaling but eliminating the protein strengthens the signaling.
“When synapses get stronger, we learn. When they get weaker, we forget,” said Featherstone. “We discovered that tomosyn can control whether synapses get stronger or weaker, and this appears to be important in memory formation.”
David Featherstone. Photo by Roberta Dupuis-Devlin
Experiments conducted in the lab of their collaborator, Martin Schwärzel, looked at fruit flies’ ability to learn to associate a particular odor with an electrical shock. Richmond explained that the flies did remember the association and avoided the odor for hours after the shock. However, when tomosyn was knocked out, “the flies were unable to retain the memory,” she said.
Featherstone and Richmond hope their findings—which demonstrated how tomosyn can affect synaptic signaling, learning and memory—will provide valuable clues that pharmacologists can use to create new drug therapies for various forms of human memory loss.
The work was funded by the National Institutes of Health and the Alexander von Humboldt Foundation. Co-authors included Martin Schwärzel and Antje Richlitzki of the Free University of Berlin Institute for Biology/Genetics. Kaiyun Chen, former research assistant professor in the UIC Featherstone Laboratory, served as electro-physiologist for the study.
Elizabeth Abrams. Photo by Micki Leventhal
Elizabeth Abrams, assistant professor in the Department of Anthropology, teamed up with Julienne Rutherford, assistant professor of oral biology in the UIC College of Dentistry and adjunct assistant professor in anthropology, to co-author an evolutionary analysis of human vulnerability to postpartum hemorrhage, the leading cause of maternal mortality worldwide. Postpartum hemorrhage accounts for nearly 35 percent, or 125,000, of the 358,000 maternal deaths that occur each year worldwide. Many studies on postpartum hemorrhage have focused on treatment and risk factors, but this is the first paper that examines why, from an evolutionary perspective, humans are so susceptible to it. The work was published in the journal American Anthropologist. An article on this work is also forthcoming in Textbook of Postpartum Hemorrhage, second edition.
Human babies are relatively larger and bigger-brained than those of non-human primates, yet our gestation length is not significantly longer. Abrams and Rutherford hypothesize that patterns of human placentation have evolved to promote sufficient nutrient transfer in utero to support fetal growth, with the unfortunate side effect of a significantly increased risk of postpartum hemorrhage. Nutrient transfer is accomplished in utero via the placental blood supply, which is dependent on the extent to which the fetal placental cells invade the maternal uterine wall. This suggests a link between the extent of invasiveness and blood loss at delivery, when the placenta separates from the uterine wall.
The authors hope that their novel perspective on the underpinnings of postpartum hemorrhage may lead to the development of an early predictor—or biomarker—of risk based on hormones or other factors produced by placental cells. Many women in poor countries don’t give birth in hospitals or clinics, explained Abrams, who has conducted research on childbirth in the sub-Saharan countries of Malawi and Tanzania. By the time postpartum bleeding occurs, it may be too late to go to a health center. A biomarker for postpartum hemorrhage “could be used early in pregnancy to assist women in making informed decisions about their choice of birthing site and medical care based on their risk,” said Abrams.
The research was funded by a Wenner-Gren Foundation grant to Abrams (and UIC anthropology colleague Crystal Patil) and a UIC Building Interdisciplinary Research Careers in Women’s Health (BIRCWH) faculty scholarship to Rutherford from the National Institute of Child Health and Human Development and the National Institutes of Health Office of Research on Women’s Health.
Wonhwa Cho. Photo by Kathryn Marchetti
Wonhwa Cho, distinguished professor of chemical biology in the Department of Chemistry, and his colleagues have created a new biosensor that measures membrane lipid levels by modifying proteins to fluoresce when they bind lipids. The methodology could open up new pathways to disease diagnosis and treatment by leading to a mechanism that would control cell-membrane fat. Their findings were published in Nature Chemistry online October 9, 2011.
Cho, who is the principal investigator for the Cho Group, explained that “lipid molecules could serve as some sort of sliding switch. These switches can turn on or off protein activities that affect diverse cellular processes, including those associated with disease.”
Cho’s advance in lipid imaging technique is the first successful quantification of membrane lipids in a living cell in real time. He has been working on the technique for about a decade, overcoming technical obstacles only about three years ago. “We had to engineer the protein in such a way as to make it very stable, behave well and specifically recognize a particular lipid,” Cho explained. He now hopes to create a tool kit of biosensors to quantify most, if not all, lipids.
Once lipid concentrations reach a certain threshold, they trigger reactions, including disease-fighting immune responses, Cho said. Quantifying lipid membrane concentration in a living cell and studying its location in real time can provide a powerful tool for understanding and developing new ways to combat a range of maladies including inflammation, cancer, diabetes and metabolic diseases.
Other authors on the paper are postdoctoral researcher Youngdae Yoon, who developed the sensor; Park J. Lee, a doctoral student who developed microscope tools to enable the lipid quantification; and doctoral student Svetlana Kurilova, who worked on the protein cell delivery. Funding was provided by the National Institutes of Health and the Chicago Biomedical Consortium.
Serdar Ogut. Photo by Juan C. Idrobo
Professor Serdar Ogut of the Department of Physics was elected as a Fellow of the American Physical Society at its November 2011 council meeting. Election to APS fellowship is limited to no more than one half of one percent of the membership. Ogut was cited for his “contributions to understanding and predicting properties of nanostructures and bulk defects, surfaces and interfaces through the development and application of first principles computational techniques.” Ogut, who is a member of the UIC Materials Modeling Group, said: “This recognition is a great honor for me as well as the UIC physics department. This is the second year in a row UIC physics faculty have been elected as APS fellows.”
Ogut’s current research projects in computational materials physics are funded by grants from the U.S. Department of Energy, the National Science Foundation, Argonne National Laboratory and the National Institute of Standards and Technology. From fall 2009 until fall 2011, Ogut was on a leave of absence from UIC working as a program director in the Division of Materials Research at the NSF in Arlington, VA. While he continues to work part-time for the NSF remotely, he has returned to UIC to continue with his regular duties of teaching, research and service. Ogut typically teaches courses in quantum mechanics and solid state physics at the graduate level. He is the recipient of several teaching awards, is the co-director of graduate studies in the physics department and serves on the Graduate College Awards Committee.
Voices of the College includes material adapted from articles that appeared in UIC News.