Professor Jennifer L. Ross,
University of Massachusetts - Amherst,
"Building the Cell with Microtubule Self-Organization"
Abstract: The cell is a complex autonomous machine taking in information, performing computations, and responding to the environment. To enable agile read/write capabilities, much of the molecular biochemistry that performs these computations must be transient and weak, allowing signals to be carried as a function of the concentration of numerous and coupled interactions. Traditionally, biochemical experiments can only measure strongly interacting systems that can last for long times in dilute concentrations. We have developed microscopy measurements to enable visualization of weak, transient interactions and the resulting emergent behaviors of coupled systems. I will present excerpts from stories where many weak, transient interactions can have strong repercussions on the overall activity and can, in fact, overpower strongly interacting systems. These studies involve the microtubule cytoskeleton, the transport motor, kinesin-1, and the microtubule crosslinker, MAP65. Our results reveal a fundamentally important aspect of cellular self-organization: weak, transient interacting species can tune their interaction strength directly by tuning the local concentration to act like a rheostat. The tunability of weak, transient interactions is a fundamental activity of biological systems, and our insights will ultimately enable us to learn how to engineer these systems to create biological or biomimetic devices.
Bio: Ross is the director of the new Massachusetts Center for Autonomous Materials (MassCAM) and an award-winning biophysicist studying the organization of the microtubule cytoskeleton and microtubule-based enzymes using high-resolution single molecule imaging techniques. She has a Ph.D. in Physics from UC Santa Barbara, and has studied the microtubule cytoskeleton for almost two decades. As a Cottrell Scholar, Ross has pioneered innovative teaching techniques that are being adopted around the world. Specifically, she has taught at several international short courses on microscopy including Analytical and Quantitative Microscopy (AQLM) at the Marine Biology Laboratory and the Bangalore Microscopy Course at the National Centre for Biological Science in Bangalore, India. She is also an advocate for women and under-represented groups and has a blog to help others succeed it in academic science.
Professor Zhibin Guan,
University of California - Irvine,
"Be Strong, Tough, Adaptive and Self-healing:
Life Lessons Applied to Dynamic Soft Material Designs"
Abstract: Many biopolymers not only have advanced mechanical properties such as high modulus, toughness, and elasticity, but more importantly, exhibit dynamic characteristics including adaptive, malleable, and self-healing properties. Following inspirations from the Nature, Guan lab has developed several families of biomimetic soft materials imbued with various dynamic properties. In one system, we have designed a series of biomimetic modular polymers with folded nano-domains as the repeat units. These new material manifest an exciting combination of key mechanical, as well as adaptive, properties that have until now proven difficult to achieve in man-made systems. In another example, we have developed strong and autonomous self-healing polymers using various supramolecular and dynamic covalent interactions. In contrast to previous designs, our system spontaneously self-heals as a single-component solid at ambient conditions without the need of any external stimulus, healing agent, plasticizer, or solvent. Recently, we have also made significant progress in adaptive, malleable thermoset polymers via dynamic covalent bond exchange. The overarching concept for all these projects is to build a direct link between miscroscopic molecular properties and macroscopic bulk performance. In this seminar, I will discuss the design, synthesis, and property studies of these dynamic adaptive polymers.
Bio: Zhibin was raised in Anhui Province, China. He went to Beijing for receiving his high education. After finishing his undergraduate and master education at Peking University, he came to the United States for Ph.D. study. He received his Ph.D. degree in 1994 at the University of North Carolina, Chapel Hill. Following a postdoctoral stint at Caltech and a short career at DuPont, in 2000 he joined the faculty of the Department of Chemistry at UC Irvine as an assistant professor. He was promoted to Associate Professor with tenure in 2004, and to Full Professor in 2006. From 2006, he also became affiliated faculty of the Department of Biomedical Engineering and the Department of Chemical Engineering and Material Science at UC Irvine. He has received recognition of his research with several awards and fellowships, including the Japan Society for the Promotion of Science (JSPS) Fellowship, the Humboldt Bessel Research Award, the Camille Dreyfus Teacher-Scholar Award, the NSF CAREER Award, the Beckman Young Investigator Award, and an elected Fellow of the American Association for the Advancement of Science. He serves as the Chair for the 2018 Bioinspired Materials Gordon Research Conference in Les Diablerets, Switzerland.
Zhibin pursues a broad range of research interests that include new polymerization chemistry through catalysis, bioinspired materials design, self-healing and dynamic materials, single molecule force study of polymers, and functional biomaterials for gene delivery and immunology. His research work has been featured many times in scientific journals and popular newspapers such as C&EN News, Washington Post, Wall Street Journal, Los Angeles Times, CNN, Forbes, etc.