Materials Science & Biophysics Research Seminar Series

Fall 2022 Seminar Series

Self-assembly of the cellular skeleton, one molecule at a time

Shashank Shekhar
Assistant Professor of Physics and Cell Biology
Emory University

Friday, September 16, 2022
2 PM - 3 PM Materials and Biophysics seminar EC 1218

Living cells employ self-assembly to build intracellular structures orders of magnitude larger than their individual constituent units. One such example is the actin cytoskeleton, formed from self-assembly of actin monomers into linear actin filaments. Cells use actin polymerization to generate forces required for processes such as cell movement, cell division and wound healing. Although the key components of the actin remodeling machinery have been identified, how they act in concert remains a mystery. Our lab combines bottom-up and top-down experimental methods with mathematical modelling to investigate how living cells integrate multicomponent molecular activities to regulate physiological actin dynamics. We employ a range of quantitative biophysical approaches such as microfluidics, multispectral single-molecule and single-filament imaging. First, I will show how a dynamic interplay between enhancers (formin) and inhibitors (capping protein) of actin polymerization leads to tunable control of actin assembly. Second, I will present a novel multicomponent mechanism comprising of two actin disassembly factors resulting in over 300 fold enhancement of actin depolymerization. These results illustrate the interplay between molecular components and mechanical forces underlying complex cytoskeleton dynamics. Our research exemplifies the power of synthetic biophysical approaches in dissecting fundamental biological mechanisms.

Complex magnetic phases in quantum materials

Dr. Binod K Rai, Ph.D
Senior Scientist A
Savannah River National Laboratory

Friday, October 28, 2022
2- 3 PM Materials and Biophysics seminar C 1218

Quantum materials, which exhibit multifaceted interactions between electrons, give rise to exciting phases with the potential for advanced functionality, such as topological magnetic textures. The stabilization of these complex magnetic phases depends on the underlying crystallographic lattice and the existence of competing interactions. My research pursues an understanding of novel magnetic states and the underlying mechanisms responsible for the emergence of collective phenomena in quantum materials by combining bulk crystal growth, thermodynamic measurements and neutron scattering. This seminar will provide an overview of topological magnetic textures and recent experiments demonstrating signatures of complex magnetic structures in tetragonal NdCoGe3 and NdCuGa3 will be highlighted. Realizing such topologically nontrivial magnetic states in crystalline materials will advance our understanding of how interactions and underlying symmetries combine to form complex magnetic states and may offer a platform for the advancement of theoretical models.

Cellular Biophysics of Neutrophils – Lessons from NETosis

Hawa Racine Thiam
Assistant Professor of Bioengineering and Sarafan ChEM-H Institute Scholar
Stanford University

Friday, November 11, 2022
2 PM - 3 PM Materials and Biophysics seminar EC 1218

Neutrophils are innate immune cells critical for host defense again pathogens. To accomplish their tasks, neutrophils need to build cell-scale responses to rapidly move, remodel, and interact with the microenvironment. These cell-scale functions require cells to generate and transmit physical forces. Our lab aims to understand how neutrophils generate the physical forces required for the well execution of their functions in the physically challenging in vivo environment. Such knowledge will be critical for our long-term goal of controlling neutrophils functions.