Figure 2. The C-Terminus of CFTR is required for focusing the sub-apical cytoskeleton.

(A) Typical confocal micrographs taken in X-Y mode of F-actin and NHERF1 in HEK293T cells expressing GFP-tagged wild-type or ΔTRL CFTR, or non-transfected (null). Scale bar is 25 μm. (B) Mean fluorescent intensities taken from confocal micrographs in A. All n = 15. (C) Typical super resolution images of wild-type and ΔTRL CFTR (green) expressed in HEK293T cells and counter-stained for F-actin using phalloidin-647 (red). Each pixel is 30 nm² and the scale bar is 2.5 μm. Arrow denotes plasma membrane wild-type CFTR. All data are representative from images acquired on three separate occasions. The corresponding brightfield images are also shown and the regions imaged in super resolution mode are boxed. (D) Pearson’s correlation coefficient (r) for colocalization between wild-type or ΔTRL CFTR and F-actin, based on images shown in C. *p < 0.05 different ± CFTR expression. ^†p < 0.05 different to 0.