Fig. 4.

TJs are remodeled in response to tissue-scale changes in tension over longer and shorter periods of time. (A) Sustained global remodeling of TJs through genetic manipulation – specifically ZO-1 and ZO-2 double knockdown. In epithelial cells, double knockdown of ZO-1 and ZO-2 increases the accumulation of perijunctional actomyosin, and cells exhibit increased paracellular flux of large solutes (not illustrated). A magnification of the boxed area is shown below, showing this region before (top) and after (bottom) double knockdown of ZO-1 and ZO-2. (B) Acute global remodeling of TJs through mechanical stimuli. Mechanical stretching of epithelial tissue (indicated by black arrows) also increases accumulation of perijunctional actomyosin, and cells exhibit barrier leaks (not shown). A magnification of the boxed area is shown below, showing this region before (top) and after (bottom) stretch. See text for additional details.