Development of functional tight junctions. (A-D) Cells were plated and incubated without or with tetracycline as described in figure 1. After switching from low calcium to normal calcium medium, TER was measured at the indicated time points. Shown is a typical experiment using a control RNAi cell line (A), a ZO-1 RNAi cell line (B), and two Apg-2 RNAi cell lines (C and D). Values represent means +/- 1 SD of quadruplicates. (E) Paracellular permeability of fluorescent dextran was measured in the same cultures as those shown in panels A to D 3 days after the initiation of junction formation. Shown are the values obtained with 4 kD FITC dextran with tetracycline-treated cultures. Values represent means +/- 1 SD of quadruplicates. Diffusion of 70 kD dextran was also not affected by depletion of Apg-2 and ZO-1 (not shown).
Aijaz et al. BMC Cell Biology 2007 8:49 doi:10.1186/1471-2121-8-49