James Chen to present 2016 Ramon and Victoria Lim Medical Science Lecture

The UI Carver College of Medicine will welcome Zhijian “James” Chen, the George L. MacGregor Distinguished Chair in Biomedical Science at the University of Texas Southwestern, on Monday, April 18, as he presents the 2016 Ramon and Victoria Lim Medical Science Lecture. Chen’s lecture, “Enemy Within – Innate Immune Sensing of Cytosolic DNA by the cGAS-STING Pathway,” will be held at 12:00 p.m. in the Urmila Sahai Seminar Room (2117 MERF). A discussion will follow the lecture at 1:00 p.m. in 2126 MERF.

The Ramon and Victoria Lim Medical Lectureship Fund was created in 2004. The fund supports the visits to Iowa City of eminent scientists working in neuroscience and internal medicine. Ramon Lim, MD, PhD, is a UI professor emeritus of neurology and a researcher in the area of brain proteins and brain cell biology. Victoria Lim, MD, is a UI professor emeritus of internal medicine who studied endocrine disorders in patients with kidney disease.

James Chen received an undergraduate degree in biology at Fujian Normal University in China. After placing first on a biochemistry exam, Chen won an overseas scholarship at the State University of New York at Buffalo, where he earned a PhD in biochemistry. After a year of post-doctoral work with the Salk Institute, Chen worked as a senior scientist at ProScript, a biotech firm that is now part of Millennium Pharmaceuticals. In 1997, he was recruited to the University of Texas Southwestern Medical Center where he currently serves as professor of molecular biology and the George L. MacGregor Distinguished Chair in Biomedical Science.

While at ProScript, Chen began studying ubiquitin, a small protein that was thought to serve mainly as a tag for marking proteins for degradation by the proteasome - the cellular equivalent of a garbage disposal. His work enabled optimization of assays for proteasome inhibitors including Velcade, which was approved by the Food and Drug Administration in 2003 for the treatment of multiple myeloma.

Since then, Chen has discovered an additional and unexpected role for ubiquitin in directly activating protein kinases. His current research focuses on mechanisms of cell signaling and innate immunity, particularly how cells detect foreign DNA or RNA due to microbial infection in order to mount an appropriate immune response. The Chen laboratory has identified ubiquitin as an important regulator of the pathway by which cytosolic RNA sensing by RIG-I proteins leads to transcription of genes involved in immune and inflammatory responses. Most recently, they solved the longstanding mystery as to how host cells recognize and respond to foreign DNA. Chen and his group discovered an enzyme called cyclic GMP-AMP synthase (cGAS). Upon binding to foreign DNA, cGAS is activated to catalyze the synthesis of a unique isomer of cyclic GMP-AMP (2'3'-cGAMP). cGAMP functions as a second messenger that leads to the activation of a signaling cascade to induce interferons and cytokines. His research collectively has profound implications for our understanding of autoimmune disease and antitumor immunity, and has provided important insights into novel therapeutic targets for vaccines and immunotherapy.

Chen is a Howard Hughes Medical Institute Investigator and a member of the National Academy of Sciences. He has received the National Academy of Sciences Award in Molecular Biology, the Norman Hackerman Award in Clinical Research from the Welsh Foundation and the Edith and Peter O’Donnell Award in Science from the Academy of Medicine. The American Society for Biochemistry and Molecular Biology also honored Chen with the Merck Award for his outstanding contributions to the field.

Story Source: Benji McElroy, UI Carver College of Medicine, 200 College of Medicine Administration Building, Iowa City, Iowa 52242

Media Contact: Jennifer Brown, UI Health Care Marketing and Communications, jennifer-l-brown@uiowa.edu