Abstract:
:Many complex cellular processes from mitosis to cell motility depend on the ability of the cytoskeleton to generate force. Force-generating systems that act on elastic cytoskeletal elements are prone to oscillating instabilities. In this work, we have measured spontaneous shape and movement oscillations in motile fish epithelial keratocytes. In persistently polarized, fan-shaped cells, retraction of the trailing edge on one side of the cell body is out of phase with retraction on the other side, resulting in periodic lateral oscillation of the cell body. We present a physical description of keratocyte oscillation in which periodic retraction of the trailing edge is the result of elastic coupling with the leading edge. Consistent with the predictions of this model, the observed frequency of oscillation correlates with cell speed. In addition, decreasing the strength of adhesion to the substrate reduces the elastic force required for retraction, causing cells to oscillate with higher frequency at relatively lower speeds. These results demonstrate that simple elastic coupling between movement at the front of the cell and movement at the rear can generate large-scale mechanical integration of cell behavior.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Barnhart EL,Allen GM,Jülicher F,Theriot JAdoi
10.1016/j.bpj.2009.10.058subject
Has Abstractpub_date
2010-03-17 00:00:00pages
933-42issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(09)06003-2journal_volume
98pub_type
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