|
Fig. 5 Chemokine-directed polarity establishment. (A) A scheme presenting the generation of local chemokine source within the live embryo. (B–D) Apolar cells (Left), the emergence of the polarized front (time 00:00) (Middle), and the subsequent polarized localization of the rear markers (Right). Lifeact is labeled with magenta and rear markers (B) Ezrin, (C) Esyt2a, and (D) MTs (Clip170H) are in green. White arrows indicate the direction of migration toward the chemokine source. Time is in minutes and seconds. (Scale bar, 10 µm.) (B′–D′) Time course of polarity index establishment during cell polarization; time is in seconds. For B′ and C′ the signal was measured only at the level of the membrane. In B–D the distribution of the chemokine (Cxcl12a) is illustrated by the red gradient below the panels. (E) Timing of the chemokine induced polarization steps relative to the time of actin localization at the cell front (time 0) (median, 5 and 95 percentiles are presented, n = number of cells, time in seconds).