Skip to main content
. Author manuscript; available in PMC: 2010 Jun 14.
Published in final edited form as: Nature. 2009 Aug 19;461(7260):99–103. doi: 10.1038/nature08242

Figure 4. Spatiotemporal coordination of Rac1, Cdc42, and RhoA activation.

Figure 4

(a) Timing of Rho GTPase activation relative to edge velocity, as determined by temporal cross-correlation functions. The variable ‘edge movement’ is being used as the reference signal. Thus, correlation maxima in the sector labeled “After” indicate that the GTPase reaches the activation maximum after the protrusion event (time point of fastest edge advancement). Dashed lines: 95% confidence intervals. Data originate from n = 11 cells (Rac1), n = 12 cells (Cdc42), and n=12 cells (RhoA). Confidence intervals were computed by bootstrap sampling of 2000 residuals to the spline fits. (b) Timing of RhoA activity relative to Cdc42 activity, both monitored in the same cell, as determined by the temporal cross-correlation function. The variable Cdc42 is being used as the reference signal. Thus, the correlation maximum in the sector labeled “Before” indicates that RhoA reaches the activation maximum before Cdc42 (n = 7 cells). (c) Model of GTPase activation during protrusion and retraction. Green: Rac1 activation. Black: RhoA activation. Blue: Cdc42 activation.