Monday, November 14, at 12:10 p.m. in Todd 334
The Gene and Linda Voiland School of Chemical Engineering and Bioengineering are hosting a seminar presented by Dr. Sarah Hitchcock-DeGregori, Dept. of Pathology and Laboratory Medicine at the Robert Wood Johnson Medical School at Rutgers University.
Sarah Hitchcock-DeGregori received her Ph.D. at Case Western Reserve University in 1970 where she studied muscle development. Her postdoctoral training was with Andrew Szent-Gyorgyi at Brandeis University and Hugh Huxley at the Laboratory of Molecular Biology in Cambridge, England. Her work with them on calcium-dependent regulation by troponin led to enduring models of the mechanism of thin filament regulation in muscle. From that time, and during her academic career at Carnegie Mellon University and Robert Wood Johnson Medical School at Rutgers University she has studied regulation of actin-dependent functions and dynamics in muscle and non-muscle systems using biochemical, biophysical and molecular approaches. She and her colleagues determined the first atomic resolution structures of tropomyosin. Her recent research has been to decipher how tropomyosin is designed to carry out its various regulatory functions. Now she is engaged in writing the biography of Hugh Huxley (1924-2013), discoverer of the sliding filament mechanism of muscle contraction.
Tropomyosin structure, function and interactions: A dynamic regulator of the actin filament
Tropomyosin is a conserved family of coiled-coil proteins that bind to filamentous actin and cooperatively regulate its function. Tropomyosin binds end-to-end along the filament, essentially “floating” on the surface allowing rapid response to upstream signals. At the pointed end of the filament it can bind to tropomodulin. Using an evolutionary approach we have identified periodic actin binding sites that alternate with sites for regulation of myosin. The myosin sites are universal or myosin isoform specific. Our results support the notion that tropomyosin specifies actin filaments for specific cellular functions, such as striated muscle contraction and intracellular transport.
