Abstract:
:It has long been appreciated that spatiotemporal dynamics of cell migration are under the control of intracellular signaling pathways, which are mediated by adhesion receptors and other transducers of extracellular cues. Further, there is ample evidence that aspects of cell migration are stochastic: how else could it exhibit directional persistence over timescales much longer than typical signal transduction processes, punctuated by abrupt changes in direction? Yet the mechanisms by which signaling processes affect those behaviors remain unclear. We have developed analytical methods for relating parallel live-cell microscopy measurements of cell migration dynamics to the intracellular signaling processes that govern them. In this analysis of phosphoinositide 3-kinase signaling in randomly migrating fibroblasts, we observe that hot spots of intense signaling coincide with localized cell protrusion and endure with characteristic lifetimes that correspond to those of cell migration persistence. We further show that distant hot spots are dynamically and stochastically coupled. These results are indicative of a mechanism by which changes in a cell's direction of migration are determined by a fragile balance of relatively rapid intracellular signaling processes.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Weiger MC,Ahmed S,Welf ES,Haugh JMdoi
10.1016/j.bpj.2009.09.051subject
Has Abstractpub_date
2010-01-06 00:00:00pages
67-75issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(09)01565-3journal_volume
98pub_type
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