BME PhD Preliminary Exam Announcement for Md Foysal Rabbi (T. Kim, advisor) Everyone is invited to attend the public presentation beginning at 10:00am. Title: Roles of Catch-Slip Bond Dynamics at the Cytoskeleton, Cell, and Tissue Levels Date: Monday, December 2, 2024 Time: 10:00 am Location: MRGN 129 / Zoom Link: https://purdue-edu.zoom.us/j/94668271827<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpurdue-edu.zoom.us%2Fj%2F94668271827&data=05%7C02%7Cbmeroundtable-list%40ecn.purdue.edu%7C2d549ee751aa4c7bfb6908dd08e1aed7%7C4130bd397c53419cb1e58758d6d63f21%7C0%7C0%7C638676487573876371%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=qX0eumFnxh5x06RnzWcqG%2BF11%2BUqehr3exSkIFZX90s%3D&reserved=0> Thesis Committee Members: Dr. Taeyoon Kim (Chair), Dr. Sherry L. Harbin, Dr. Fang Huang, and Dr. Hector Gomez Abstract: The actin cytoskeleton, a semiflexible polymer network, serves as a critical structural and mechanical component in cells, driving processes such as migration, intracellular transport, and force generation. The mechanical resilience and adaptability of the cytoskeleton are modulated by transient protein cross-linkers, whose force-dependent dissociation dynamics dictate the network's response to external and internal stresses. Using computational modeling this work explores the interplay between cytoskeletal dynamics, myosin motor activity, and extracellular matrix (ECM) remodeling in cellular processes such as migration, invasion, and tissue remodeling. We demonstrate that cross-linkers exhibiting catch-slip bond behavior redistribute toward regions of high force, enhancing network resistance to stress and enabling myosin motors to generate greater contractile forces. In contrast, slip-bond cross-linkers migrate toward low-force regions, resulting in weaker networks. Additionally, we uncover that networks with fewer, larger myosin filaments exhibit superior mechanical stability by concentrating forces into specific regions, promoting efficient cross-linker redistribution and stress propagation. Using our cell-ECM interaction model we expect to uncover how focal adhesion dynamics and force transmission remodel the ECM anisotropically, aligning fibers radially to support invasive behavior. Enhanced catch-slip bond characteristics strengthen focal adhesion-mediated force transmission, emphasizing their role in anisotropic ECM remodeling and directional cellular processes. Together, these studies provide mechanistic insights into cytoskeletal and ECM mechanics, highlighting the synergy between molecular-scale interactions and large-scale structural organization. These findings not only deepen our understanding of cellular behavior in dynamic environments but also inform the design of biomimetic materials with tunable mechanical properties. -- Bmeroundtable-list mailing list Bmeroundtable-list@ecn.purdue.edu https://engineering.purdue.edu/ECN/mailman/listinfo/bmeroundtable-list