Fig. 4: Increasing the abundance of the actomyosin cortex using RacE leads to signaling inhibition.
From: Complementary cytoskeletal feedback loops control signal transduction excitability and cell polarity
a Scanning confocal imaging of RacE-GEF (mCherry-FRB-GXCTΔNT) membrane recruitment and cell shape in wild type (AX3) Dictyostelium cells. Cells are also expressing an unlabeled membrane-localized FKBP domain (cAR1-2xFKBP). t = 00:00 indicates rapamycin addition. b Temporal color projections of cell outlines corresponding to the movie in a. Blue and yellow times indicate the first and last images in the projection, respectively. c Average (line) and SEM (shaded area) of cell area in AX3 cells before and after GXCT recruitment (dashed line, t = 0). n = 35 cells. d Traces of cell movement in AX3 cells 200 seconds before and after GXCT recruitment. n = 35 cells. e Scanning Confocal imaging of GXCT recruitment and polymerizing actin (LimEΔCoil-EGFP) in AX3 cells. t = 00:00 indicates rapamycin addition. f Membrane kymograph of LimE from the movie in e. Dashed line indicates rapamycin addition, scale bars = 2 minutes (horizontal) and 5 µm (vertical). g Average and SEM membrane-to-cytosol ratio of LimE before and after GXCT recruitment by rapamycin addition (dashed line, t = 0). n = 8 cells. h Scanning Confocal imaging of GXCT recruitment and Ras activation (RBD-EGFP) in AX3 cells. t = 00:00 indicates rapamycin addition. i Membrane kymograph of RBD from the movie in h. Dashed line indicates rapamycin addition, scale bars = 2 minutes (horizontal) and 5 µm (vertical). j Average and SEM membrane-to-cytosol ratio of RBD before and after GXCT recruitment by rapamycin addition (dashed line, t = 0). n = 9 cells. Time is in min:sec. Scale bars = 5 µm unless otherwise noted. Source data are provided as a Source Data file.
