FIGURE 1:

p115RhoGEF localizes to Rho flares during TJ remodeling. (A) Cells expressing fluorescently tagged candidate RhoGEFs (p115RhoGEF.S-mNeon, p115RhoGEF.L-mNeon, LARG.L-mNeon, PDZRhoGEF.S-mNeon, and p114RhoGEF.S-mNeon), active RhoA probe (mCherry-2xrGBD), and fluorescently tagged ZO-1 (BFP-ZO-1). All are shown in Fire LUT. The data for each RhoGEF were acquired with the same settings, and the LUTs were adjusted in the same way for each GEF, with the noted differences in LUT scaling for the three different probes. Loss of ZO-1 (white arrows) corresponds to sites of active RhoA flares (white arrowheads). Yellow arrowheads indicate sites of Rho flares in tagged candidate RhoGEF images. (B) Time-lapse montage of junction indicated by the white dashed boxes in A. Local increase in p115.S (yellow arrowheads) occurs at site of ZO-1 loss (white boxed regions enlarged below). p115.S signal intensity peaks with the peak of active RhoA (white arrowheads). Time 0 represents the start of the Rho flare increase. Fire LUT applied to all three probes without enhanced brightness and contrast. (C) Mean normalized intensity of p115.S, active RhoA, and ZO-1 at sites of ZO-1 loss, quantified from B and additional videos; p115.S signal intensity peaks with or slightly before the peak of active RhoA. Shading represents SEM. n = 15 flares, 5 embryos, 4 experiments.