Fig. 3.

The role of Rho GTPases in controlling protrusion type formation. (A,B) Normalized whole-cell FRET-based activity measurement of RhoA (A) and Rac1 (B). The graphs show the median; whiskers indicate the interquartile range (IQR). A two-tailed t-test was used in A; a Mann-Whitney test was used in B. Scale bars: 15 ?m. (C) Normalized whole cell FRET-based myosin light chain phosphorylation levels. The graph shows the median; whiskers indicate the interquartile range (IQR). Two-tailed t-test was performed. (D) Representative images of actin flow in PGCs migrating within ectodermal and mesodermal tissues. Kymographs derived from the middle of the cell. Scale bar: 15 µm. (E) Retrograde actin flow speed (V). The graph shows the median; whiskers indicate the interquartile range (IQR). Two tailed t-test was performed. (F,H) Representative examples of ezrin-YPet distribution in PGCs residing within converted embryos (F) or in PGCs expressing control RNA or low levels of RNA encoding a constitutively active form of RhoA (H). Scale bars: 15 µm. (G,I) Schematic representation of cortical ezrin distribution around the cell perimeter (left). Cortical ezrin signal was masked and sliced in an angular manner, and the results are presented in the graphs. For each cell, ezrin intensity was normalized to the peak intensity in the cell. Colored dots and solid lines represent the means; dashed lines represent the standard deviations. A Kolmogorov?Smirnov test was performed to compare frequency distributions. N and n represent numbers of embryos and cells, respectively.