Fig. 6
IQGAP1 interaction with Hax1 regulates focal adhesion dynamics. A, Representative immunofluorescence images of mock, Hax1 or IQGAP1 knockdown (KD) MCF7 cells stained for FA marker vinculin (green). Scale bar, 10 μm. B, Box and whisker plot indicating the size distribution of focal adhesions in mock, Hax1 or IQGAP1 KD cells (50 focal adhesions were analyzed for each genotype). Knockdown of Hax1 or IQGAP1 leads to a significant increase in focal adhesion size compared with mock cells (p < 0.0001 and p < 0.001 respectively, Student’s t test). C, Representative time-lapse images (montages) of DsRed-Zyxin-expressing MCF7 cells. Note the formation and dissolution of focal adhesions in mock cells and very static focal adhesion in Hax1 or IQGAP1 KD cells. Scale bar, 10 μm. D, Box and whisker plots revealing slow assembly and disassembly rates of focal adhesions in Hax1 or IQGAP1 KD cells relative to their mock counterparts. For each genotype, 50 focal adhesions were analyzed. Knockdown of Hax1 or IQGAP1 leads to a significant decrease of focal adhesion assembly and disassembly rate compared with mock cells (p < 0.0001 and p < 0.001 respectively, Student’s t test). E, FRAP was used to visualize reduced dynamics of FAs in mock, Hax1 or IQGAP1 KD cells Representative time-lapse images (montage) of FAs are shown. Scale bar, 10 μm. F, Box-and-whisker diagram quantifying the differences in half-time (T1/2) of FRAP between mock and KD cells (n > 10, p < 0.01 and p < 0.05 respectively, Student’s t test)