Speaker: Dr. George Shubeita, Assistant Professor of Physics at University of Texas, Austin
Topic: “Molecular Motors: from Mechanics to Disease”
Time: 11:00 am, Monday, March 3, 2014
Place: P-148 (refreshments will be served at 10:45 in P-145A)
Abstract:
Much like a city, living cells are organized, and maintaining their organization is essential for their proper functioning. To position micrometer-sized vesicles and organelles inside the cell at the right place and in a timely fashion the cell shuttles these cargoes along a network of intracellular roads (microtubules and actin filaments) using a set of molecular motor proteins (kinesin, dynein and myosin). These motor proteins use the energy released by ATP hydrolysis to generate the force they need to haul the cargoes; thus, measuring that force amounts to directly probing their function. Measuring the piconewoton forces that motors exert in their native cellular environment enabled us to count the number of motors hauling individual cargoes, and to test physical models of intracellular transport. Given the ubiquity of molecular motors, failure in regulating their function can result in disease. Neuro degenerative diseases such as Alzheimer’s, Huntington and Amyotrophic Lateral Sclerosis, for example, have been linked to motor malfunction. Using a combination of genetic, biochemical and biophysical tools in a fruit fly model of Alzheimer’s disease, we established the mechanism by which the motor regulator GSK-3 alters transport when present in the elevated levels found in Alzheimer’s patients. Our findings have implications on the development of Alzheimer’sdrugs targeting GSK-3.