An Elmo–Dock complex influences GTPase activity at cell–cell contacts. (A) Montage of images from movies of live-cells expressing the Rac FRET sensor and treated with scramble or Elmo2 siRNA. Asterisks indicate Rac-positive lamella, and yellow arrows indicate the boundary of the cell–cell contact. (B) Montage of images from videos of live cells expressing the RhoA FRET sensor and treated with scramble or Elmo2 siRNAs. Asterisks indicate RhoA-positive lamellipodia. Yellow and white arrowheads mark expanding cell–cell contacts in black/white and color images, respectively. (C) Mean Rac (top) and RhoA (bottom) FRET pixel intensity in scramble and Elmo2 siRNA-treated cells. Mean pixel intensity per unit area was quantified for 8–10 cell–cell contacts per condition. Results are presented in a box and whisker format, in which the ends of the box mark the upper and lower quartiles, the horizontal line in the box indicates the median, and the whiskers outside the box extend to the highest and lowest value within 1.5× the interquartile range: *, P < 0.01; **, P < 0.0002 (Mann–Whitney test). A.U., arbitrary unit. (D) Model of Elmo–Dock complex function during cadherin–integrin cross talk. Bars, 5 µm.