Fig. 2.

Junctions with 4 cells increase in NKCC1-DFX-expressing cells. A: picture showing multiple 3-cell junctions in MDCK cells transfected with wild-type NKCC1 cDNA. B: picture showing a 4-cell junction and multiple 3-cell junctions in MDCK cells transfected with mutant NKCC1-DFX cDNA. C: quantitation: 12 photographs each were analyzed and cells junctions were counted in MDCK cells expressing wild-type or mutant cotransporter. As shown by the box-and-whisker plot, the majority of junctions tie 3 cells (94.3% in wild-type and 85.5% in mutant cells). The number of 4-cell junctions more than doubles (5.2% to 11.5%) in the mutant transporters (12 images from 12 independent experiments and 406 junctions per condition). MDCK, Madin-Darby canine kidney; NKCC1, Na⁺-K⁺-2Cl⁻ cotransporter-1.