Portal de Periódicos da CAPES

Mechanism of shape determination in motile cells

2008; Nature Portfolio; Volume: 453; Issue: 7194 Linguagem: Inglês

10.1038/nature06952

1476-4687

Kinneret Keren, Zachary Pincus, Greg M. Allen, Erin L. Barnhart, Gerard Marriott, Alex Mogilner, Julie A. Theriot,

Corneal surgery and disorders

The shape of motile cells is determined by many dynamic processes spanning several orders of magnitude in space and time, from local polymerization of actin monomers at subsecond timescales to global, cell-scale geometry that may persist for hours. Understanding the mechanism of shape determination in cells has proved to be extremely challenging due to the numerous components involved and the complexity of their interactions. Here we harness the natural phenotypic variability in a large population of motile epithelial keratocytes from fish (Hypsophrys nicaraguensis) to reveal mechanisms of shape determination. We find that the cells inhabit a low-dimensional, highly correlated spectrum of possible functional states. We further show that a model of actin network treadmilling in an inextensible membrane bag can quantitatively recapitulate this spectrum and predict both cell shape and speed. Our model provides a simple biochemical and biophysical basis for the observed morphology and behaviour of motile cells. Cell shape is determined by the interaction of many elements such as the cytoskeleton, cell membrane and interaction of cells with their substrate. Keren et al. have analysed the natural cell-to-cell variability in a large population of motile cells (keratocytes) from fish skin to reveal mechanisms of shape determination. They develop a model that accurately predicts both cell shape and speed based on a physically realistic, molecularly detailed model of an actin network treadmilling in an inextensible membrane bag. Theriot and colleagues use fish keratocytes to study variations in cell shape that occur during motility. They report a model that quantitatively accounts for their experimental measurements and provides an explanation for the observed morphology of motile cells.