BME PhD Defense Announcement for Jing Li (T. Kim, advisor) Everyone is invited to attend the public presentation beginning at 9:30am EST. Title: A Computational Study of Cortical Cytoskeletal Remodeling during Cell Morphogenesis Date: November 12, 2021 Time: 9:30am EST Link: Join Zoom Meeting https://purdue-edu.zoom.us/j/92336892342?pwd=eXlpemM2Smx3aDJ3bVI4VjRaRXV5Zz0... Meeting ID: 923 3689 2342 Passcode: 964895 Committee: Dr. Taeyoon Kim, Chair Dr. David Umulis Dr. Daniel Szymanski Dr. Daniel Suter Abstract: During development in both animals and plants, cell morphogenesis is fundamental to various aspects of cellular functions, including contractility, motility, and their ability to respond to physiological and mechanical stimuli. The cell cortex, consisting of actin and microtubule cytoskeletons, plays a critical role in the spatiotemporal regulation of cell morphogenesis. Remodeling of the cytoskeleton is responsible for a large fraction of morphogenetic processes. However, due to experimental limitations, the underlying mechanism of the remodeling of the cortical cytoskeleton remains elusive. These limitations can be overcome by computational models. We computationally investigated two systems: the actin cytoskeleton in animal cells and cortical microtubule arrays in plant cells. For the actin cytoskeleton, we implemented a well-established agent-based model consisting of inter-connected cylindrical segments representing actin filaments, actin crosslinking proteins, and molecular motors. We found that the active remodeling of actin networks is regulated by network connectivity as well as the dynamic behaviors of crosslinking proteins and motors. In addition, we demonstrated that the fragmentation (i.e., severing) and turnover of actin filaments mediate various clustering behaviors due to a balance between force generation and force relaxation. For microtubule arrays, we developed a coarse-grained model of microtubules based on the Gillespie algorithm. Using the model, we studied the self-organization of the cortical microtubule arrays in response to tensile stress. By implementing a cellular stress pattern and a constitutive relationship between stress and plus-end dynamics of microtubules, we were able to identify the most sensitive parameters that constitute dynamic instability and recapitulate a distinct morphological transverse band. We further validated the importance of branched nucleation and severing during bundle formation and network evolution. Overall, our results regarding the two cytoskeleton systems provide insights into understanding the precise control of cytoskeletal remodeling at subcellular scales as well as integrative molecular mechanisms underlying cell morphogenesis. Taeyoon Kim is inviting you to a scheduled Zoom meeting. Topic: Jing Li's final exam Time: Nov 12, 2021, 9:30 AM EST Join Zoom Meeting https://purdue-edu.zoom.us/j/92336892342?pwd=eXlpemM2Smx3aDJ3bVI4VjRaRXV5Zz0... Meeting ID: 923 3689 2342 Passcode: 964895 One tap mobile +12532158782,,92336892342#,,,,*964895# US (Tacoma) +13017158592,,92336892342#,,,,*964895# US (Washington DC) Dial by your location +1 253 215 8782 US (Tacoma) +1 301 715 8592 US (Washington DC) +1 312 626 6799 US (Chicago) +1 346 248 7799 US (Houston) +1 646 558 8656 US (New York) +1 669 900 6833 US (San Jose) Meeting ID: 923 3689 2342 Passcode: 964895 Find your local number: https://purdue-edu.zoom.us/u/avUDuzr8C -- Bmeroundtable-list mailing list Bmeroundtable-list@ecn.purdue.edu https://engineering.purdue.edu/ECN/mailman/listinfo/bmeroundtable-list