Figure 2.

The type III effector TarP localizes to focal adhesions and is sufficient to increase focal adhesion numbers when ectopically expressed. A, CtrL2-infected MEF cells were immunostained for a rabbit polyclonal antibody to TarP and a mouse mAb to either talin or vinculin. Inclusions were visualized by staining with DAPI and are marked with asterisks in the composite image. TarP localized to talin-positive FAs as well as central vinculin-positive FAs in infected, but not in mock-infected controls. Scale bar, 10 μm. B, representation of C. trachomatis effector protein TarP and its known domains fused to mTurquoise2 fluorescent protein. C, COS7 cells expressing different deletion derivatives of TarP or vector only were processed for immunofluorescence with anti-paxillin antibody to visualize focal adhesions. Representative images are shown. Scale bar, 10 μm. D, focal adhesion numbers were counted using the particle-counting plug-in in ImageJ. Data are focal adhesion number per cell and illustrated as a box-whisker plot. Whiskers represent the lowest and highest data point still within 1.5 times the interquartile range. For statistical analyses, the Wilcoxon rank sum test was used to determine significance when compared with vector-only control (*, p < 0.05).