BEGIN:VCALENDAR VERSION:2.0 PRODID:-//talks.cam.ac.uk//v3//EN BEGIN:VTIMEZONE TZID:Europe/London BEGIN:DAYLIGHT TZOFFSETFROM:+0000 TZOFFSETTO:+0100 TZNAME:BST DTSTART:19700329T010000 RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:+0100 TZOFFSETTO:+0000 TZNAME:GMT DTSTART:19701025T020000 RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU END:STANDARD END:VTIMEZONE BEGIN:VEVENT CATEGORIES:Isaac Newton Institute Seminar Series SUMMARY:Modeling of Cell Movement on Adhesive Substrates - Aronson\, I (Argonne National Laboratory) DTSTART;TZID=Europe/London:20130628T110000 DTEND;TZID=Europe/London:20130628T114500 UID:TALK45985AThttp://talks.cam.ac.uk URL:http://talks.cam.ac.uk/talk/index/45985 DESCRIPTION:Modeling the movement of living motile cells on su bstrates is a formidable challenge\; regulatory pa thways are intertwined and forces that influence c ell motion on adhesive substrates are not fully qu antified. Here\, we present a mathematical model c oupling cell shape dynamics\, treated in the frame work of the Ginzburg-Landau-type equation for auxi liary mass density (phase field)\, to a partial di fferential equation describing the mean orientatio n (polarization of actin filaments) of the cell's cytoskeletal network. In order to maintain the tot al area of the cell\, the phase field equation is subject to a global conservation constraint. Corre spondingly\, the equation for mean polarization in corporates key elements of cell mechanics: directe d polymerization of actin network at the cell memb rane\, decay of polarization in the bulk of the ce ll\, and formation of actin bundles (stress fibers ) in the rear. The model successfully reproduces t he primary phenomenology of cell motil ity: discon tinuous onset of motion\, diversity of cell shapes and shape oscillations\, as well as distribution of traction on the surface. The results are in qua litative agreement with recent experiments on the motility of keratocyte cells and cell fragments. T he asymmetry of the shapes is captured to a large extent in this simple model\, which may prove usef ul for the interpretation of recent experiments an d predictions of cell dynamics under various condi tions. We also investigate effects of adhesion and substrate elasticity on the shape and dynamics of moving cells. We demonstrate that on hard adhesiv e substrates the cells exhibit steady-state motion . A transition to stick-slip motion is observed on soft and weakly adhesive surfaces. \n