Fig 6.

RalB D49N effector mutant with impaired RalBP1 binding fails to rescue invadopodium formation in PDAC cells expressing RalB-specific shRNA. Western blot analysis of lysates from CFPAC-1 (A) and PANC-1 (B) cells expressing GFP shRNA (GFPi), RalB-specific shRNA (RalBi), and either an empty vector or wild-type (WT), D49E, or D49N RalB. (C) Number of invadopodia per cell. (D) Percentage of invadopodium-positive cells per field. Ten fields (containing 15 to 40 cells each) per condition were used for all quantitation. Statistically significant differences between RalB-specific shRNA/vector and RalB-specific shRNA/WT or D49E RalB cells, as determined by a Mann-Whitney U test, are indicated by an asterisk (P value < 0.005). Data are means ± SEM. Data shown are representative of three independent experiments.