Fig. 6.

YFP-Cldn-3 and YFP-Cldn-4 do not disrupt other endogenous tight junction proteins. Primary rat alveolar epithelial cells were transduced on day 4 with YFP-Cldn-3 (A–C, G–I, M–O) or YFP-Cldn-4 (D–F, J–L, P–R), further incubated for 2 days, and then fixed and analyzed by immunofluorescence microscopy for Cldn-7 (B, E), Cldn-18 (H, K) or ZO-1 (N, Q). As previously described (29), distribution of Cldn-7 was more irregular than Cldn-18 or ZO-1, which exhibited a more uniform labeling of tight junctions. Induced expression of YFP-Cldn-3 or YFP-Cldn-4 had little effect on localization of these endogenous tight junction proteins. Scale bars, 10 μm.