Figure S2. L. monocytogenes Invasion and Listeriopods Are Unaffected by Palladin Depletion.

HeLa cells were treated with non-targeting control (Ctrl) or palladin-targeted (KD) siRNA sequences and infected with wild type L. monocytogenes.

(A) HeLa cells were fixed following 3 hour infections and stained with a mouse monoclonal palladin targeting antibody (green), DAPI (blue) to visualize DNA and Alexa594-phalloidin (red) to visualize actin. Bacterial internalization efficiency was analyzed by counting and comparing the number of total internalized bacteria in Ctrl and KD (no detectable palladin observed by immunofluorescence microscopy) cells. In 3 independent experiments, 951 bacteria were counted in a total of 10 Ctrl cells and 822 bacteria were counted in a total of 10 KD cells; for each experiment all counts were normalized to the Ctrl counts. Data depicts percentage of bacteria invasion compared to Ctrl cells.

(B) Palladin-depleted cells were fixed following 6 hour infections and stained with a mouse monoclonal palladin targeting antibody (green), DAPI (blue) to visualize DNA and Alexa594-phalloidin (red) to visualize actin. Listeriopod formation (arrow) is unaffected by palladin depletion. Insets depict enlargement of region indicated by arrow and shows listeriopod of interest (open arrowhead). Scale bars, 5 µm and 1 µm (insets).