Speaker: Mohan Gupta, assistant professor in the Iowa State University Department of Genetics, Development and Cell Biology

Title: Microtubule Dynamics and Function: Exploiting a simple cell to investigate complex processes

Abstract: Microtubules are essential cytoskeletal filaments that underlie many cellular processes including mitosis, intracellular transport and nervous system development. They are comprised of the protein tubulin and can undergo dynamic cycles of polymerization and depolymerization. A critical but poorly understood aspect that allows microtubules to function in diverse biological roles is that their dynamic behavior (polymerization and depolymerization) can be tightly controlled in both space and time within the cell. To understand these complex and dynamic cellular events, we must determine the molecular mechanisms that govern microtubule behavior. The Gupta lab uses a combination of genetics, cell biology, quantitative live cell imaging and in vitro reconstitution assays to determine how microtubules function across multiple scales – from the level of single tubulin molecules to the regulation of microtubule polymer, and the integration of dynamic microtubule behavior with spatial cues and higher-order cellular processes. Higher eukaryotes have many isotypes, or variants, of tubulin and hundreds of microtubules per cell, which obscures the function and coordination of individual microtubules. Thus, because microtubules and their regulatory proteins are highly conserved, we primarily exploit the incomparable experimental tools available in the budding yeast, S. cerevisiae. Budding yeast is an ideal model. It is genetically tractable, biochemically accessible, utilizes minimal isotypes and, strikingly, the regulation of individual microtubules can be visualized while performing discrete cellular tasks. By exploiting this simple model, we have uncovered fundamental mechanistic insights and novel paradigms in multiple areas, including how individual microtubules are differentially controlled, how defects in microtubule function underlie human disease, and how dynamic microtubules ensure accurate chromosome segregation in mitosis. Our ongoing efforts to elucidate how microtubules are regulated in yeast, and in metazoan cells when appropriate, has fundamental implications for understanding how microtubules perform complex and essential processes in diverse organisms. Our long-term goal is to understand how microtubule functions are controlled to achieve normal growth and development, and how the underlying mechanisms can be exploited for improved human health.

Host: Yanhai Yin, GDCB chair and professor

Please join us for refreshments before the seminar outside Room 1414 of the Molecular Biology Building.