Figure 5

Phosphorylation null constructs of cortactin prevent C. jejuni induced membrane ruffling. A-T. C. jejuni induced membrane ruffling is impaired in INT 407 cells transfected with cortactin S405A, S418A or S405/418A phosphorylation null constructs. Representative confocal microscopy images of INT 407 cells uninfected (Panel A-D) and cells infected with the C. jejuni wild-type strain with various treatment conditions. The panels represent: Wild-type cortactin-EGFP (Panel E-H), cortactin S405A phosphorylation null construct (Panel I-L), cortactin S418A phosphorylation null construct (Panel M-P), and cortactin S405/418A phosphorylation null construct (Panel Q-T). Images from left to right show, DAPI staining of cell nuclei (Panels A, E, I, M, and Q), EGFP-cortactin (Panel B, F, J, N, and R), C. jejuni staining with a polyclonal rabbit α-Campylobacter antibody and a secondary Texas-Red antibody (Panels C, G, K, O, and S), and merge of all panels (Panels D, H, L, P, and T). INT 407 cells that display extensive membrane ruffling (Panel H), and cells that display no host cell membrane ruffling (Panels D, L, P, and T). C. jejuni in contact with the host cell is shown in (Panels H-1, L-1, P-1, and T-1). Images were obtained with a 63× objective and have a 10 μM scale bar (Panels A-T). Arrows indicate C. jejuni interaction with host cells. The areas within the box highlights regions of membrane ruffling and the areas within the circles indicate regions of no membrane ruffling.