Figure 8. Filopodia are required for cellular response to polarized Cxcl12a distribution.
(A) 6–7 hpf control PGCs exhibit polarized distribution of intracellular pH as determined by the FRET efficiency of the pH sensor pH-lameleon5 protein in the cells (left). Expression of the dominant negative form of Irsp53 or overexpression of the Afap1L1a abrogates the formation of high pH in the front. The graph represents average pH-FRET ratios between the front and the rear (as indicated by the circles). The values for each cell are averages of 20 time points. (B) 8–9 hpf PGCs overexpressing Afap1L1a exhibit a decrease in Rac1 activity, as determined by differences in FRET generated by a Rac1-FRET activity reporter. Arrows indicate the direction of movement. ‘n’ indicates the number of cells analysed.