Cellular Forces Measured and Controlled by DNA-based Molecular Force Sensor & Modulator
| Date/Time: | Tuesday, 03 Feb 2015 from 4:10 pm to 5:00 pm |
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| Location: | Physics 0003 |
| Phone: | 515-294-5441 |
| Channel: | College of Liberal Arts and Sciences |
| Actions: | Download iCal/vCal | Email Reminder |
Abstract: Mammalian cells are remarkable force processors. Cells adhere through membrane protein integrins and generate forces on integrins to probe the local environment. These forces regulate many fundamental cellular functions such as cell adhesion, proliferation, migration, and ultimately stem cell differentiation and cancer progression. Because of its critical importance, integrin force has long been a central topic in the field of cell mechanics. To study integrin forces at the molecular level, I developed a DNA-based force sensor and modulator termed tension gauge tether (TGT) which quantitatively reports and controls cellular forces on integrin molecules. Using TGT, I systematically studied the ranges and physiological roles of integrin forces and discovered two distinct force regimes: cell membrane generates ~40 pN molecular force on integrins to regulate cell adhesion and spreading, while actomyosin generates >54 pN molecular force on integrins to regulate cell polarization and migration. This work demonstrated the versatility of integrins and shed light on the mechanism how cells vary integrin forces to regulate different cellular functions. TGT was also applied to study other mechano-sensitive proteins such as cadherins and Notch receptors. Overall, TGT provides a novel avenue for the study of cell mechanics at the molecular level. In the future, I will apply TGT to study a series of mechanical-involved cellular processes such as kinase activation, durotaxis, stem cell differentation and endocytosis.
Xuefeng Wang is currently a postdoctoral researcher in Taekjip Ha's lab at University of Illinois at Urbana-Champaign. He obtained B.S. and M.S. degrees in Physics from Tsinghua University, Beijing China. Then he obtained Ph.D. in physics from Purdue University where he developed optics-based biosensors for biomedical applications. His current field of interest is Biophysics with an emphasis on Cell Mechanics. During postdoctoral research, he developed a molecular force sensor named Tension Gauge Tether (TGT) and quantified integrin molecular tensions. His future research aim is to study Cell Mechanics at the molecular level using the TGT combined with the single molecule imaging technique.