Fig. 1: Isolated cells exhibit regular oscillations.

a Fluorescent tracks of fibronectin of width W = 20 μm. b1–b6 Snapshots of MDCK cells observed using phase-contrast imaging. c Kymograph of a single MDCK cell (red frame in b1) showing oscillations. d, e. Typical kymographs of a statically spreading (d) and an oscillating (e) cell plated on lines with W = 20 μm. f, g Amplitude of the oscillations measured in panel e as a function of their period (f) and as a time series (g). h Frequency of the various behaviours (oscillating, spreading and other) of isolated MDCK cells on lines of different widths. n = 61, 131 and 87 trajectories for W = 10, 20 and 50 μm from six independent experiments (2 per track width). Mean (bars) and single repeats (plus signs). i Kymograph of a MDCK cell expressing PBD-YFP, a reporter of Rac1/Cdc42 activation, hence of the cytoskeleton polarity. Individual frames are separated by 10 min. Typical behaviour observed in 2 independent experiments with PBD-YFP cells. All scale bars, 100 μm.