Seminar - How cells respond to their mechanical environment: from substrate to nucleus by Dr. Julie Ying Hui JI
Date: 23 July 2013 (Tuesday)
Time: 3:30 pm – 4:30 pm
Venue: EF305, The Hong Kong Polytechnic University
Cells in a body constantly sense and respond to their mechanical as well as their biochemical environment as they maintain proper functions such as cell differentiation, metabolism, growth, and death. Transduction of forces in cells involves membrane and cytoplasm receptors, cytoskeleton filaments, and the nuclear envelope. These signals work in unison to produce subsequent changes in gene transcription, protein regulation, and overall cell physiology. Lack of proper mechanical signals and/or impaired cellular responses are implicated in many human disease mechanisms. The endothelium, for example, provides an interface between blood flow and the vascular wall, and regions exposed to disturbed flow conditions are prone to the development of atherosclerotic lesions. On the other hand, force transduction on the nuclear surface can influence phenotypes that affect the entire body. A wide range of human diseases, including Emery-Dreifuss muscular dystrophy and Hutchinson-Gilford progeria syndrome, are caused by mutations of the nuclear lamina, a filamentous meshwork that supports nuclear structure. Impaired nuclear lamina may lead to increased susceptibility to cellular damage under mechanical stress. Thus, the ability for cells to sense and respond to their physical environment through proper mechanotransduction pathways is critical to maintaining normal cellular functions. We are investigating the effect of multiple mechanical cues such as fluid shear stress and substrate properties on endothelial cell responses. More specifically, we are interested in examining how death associated protein kinase, which plays an important role in cell apoptosis; and the glucocorticoid receptor, a nuclear transcription regulator, respond to the overall mechanical environment of the cells. To achieve our goals, we utilize advanced fluorescence imaging systems, image processing algorithms, as well as genetic, molecular, and cell biology based analytical techniques.
Dr. Ji is the Associate Professor of Biomedical Engineering, Purdue School of Engineering and Technology, at Indiana University Purdue University Indianapolis. She obtained her B.S. degree in chemical engineering from the Massachusetts Institute of Technology, and her Ph.D. degree in bioengineering from the University of Pennsylvania. She also completed her post-doctoral training at Brigham’s and Women’s Hospital in Boston. Her research interests are cellular biomechanics of the cardiovascular system. Cells are constantly experiencing multitude of mechanical forces in vivo under both normal and pathological conditions. Her laboratory is working on understainding the biological responses of vascular cells to mechanical stimuli of their micro-environment. Analysis of cellular activities include changes in cell function, morphology, and protein and genetic expressions. These studies would lead to a better comprehension of disease mechanisms and their potential therapeutics.
Dr. Ji is a member of the Biomedical Engineering Society, American Heart Association, and a lifetime member of the World Association for Chinese Biomedical Engineers.