Igoshin, OlegLevine, Herbert2022-09-282022-09-282022-052022-04-21May 2022Deng, Youyuan. "Understanding Collective Cell Motility From Modulated Single-Cell Motility Cycles." (2022) Master’s Thesis, Rice University. <a href="https://hdl.handle.net/1911/113413">https://hdl.handle.net/1911/113413</a>.https://hdl.handle.net/1911/113413Mechanical signals are believed to play a major role in organizing the collective motility of epithelial cell clusters on a substrate. A number of experimental observations in these systems await a comprehensive explanation: the interior is tensile even for clusters that expand by proliferation; the tractions on the substrate are often confined to the cluster edges; mechanical waves can propagate within the cluster; cells can spontaneously fill an annulus by proliferation and initiate unidirectional rotation around it; cell clusters can durotax much more efficiently than individual cells. We formulate a mechanical model to examine these effects. We include cell motility cycles comprised of active contraction and protrusion, and use a molecular clutch picture allowing “stalling” --- inhibition of cell contraction by external forces. By attaching cells to the substrate and to each other, and taking into account contact inhibition of locomotion, we obtain a simple picture underlying many of these findings.application/pdfengCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.collective cell motilitymolecular clutch modelcontact inhibition of locomotionmechanical wavesdurotaxisThesis2022-09-28