Dresden 2006 – wissenschaftliches Programm
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AKB: Biologische Physik
AKB 5: Cell Motility II
AKB 5.3: Vortrag
Montag, 27. März 2006, 14:45–15:00, ZEU 255
Measuring protrusion forces of locomoting cells — •Marcus Prass1, Ken Jacobson2, and Manfred Radmacher1 — 1Institute of Biophysics, University of Bremen, 28359 Bremen, Germany — 2Dept. of Anatomy and Cell Biology, University of North Carolina, Chapel Hill, USA
Cell migration is very important for cellular processes like wound healing or metastasis. Although much is known from the biological point of view on the actin-myosin machinery involved in cell migration, the exact mechanism of force generation is still unclear. One possible mechanism of force generation is the polymerization ratchet model. Here, thermal fluctuations of actin filaments are necessary for polymerization of actin filaments. Since this process effectively converts chemical energy in mechanical energy a protrusive force is generated. We have designed a cantilever-based instrument to measure directly protrusion forces at the leading edge of migrating cells. An AFM-cantilever oriented perpendicular to the substrate is deflected by a migrating keratocyte (epithelial cell prepared from trout scales). The deflection could be measured by video microscopy or at better temporal and spatial resolution using a position sensitive detector. The distance between cantilever and substrate was approximately 80 nm to guarantee that the leading edge of the lamellipodium was investigated. We will show first experimental results and discuss them in the context of existing theories.