Altered cellular trafficking of nephrin mutants A419T and C623F to the plasma membrane.

(A) Fluorescent confocal micrographs of COS-1 cells co-expressing Myc-tagged nephrin variants (red) and myristoylated-GFP as plasma membrane (PM) marker (green), counterstained with DAPI (blue) to highlight nuclei. (B) 3D digital reconstruction cross-sections and line scan analyses (regions of interest indicated with yellow lines in overlays in A) were used to score intracellular distribution of nephrin relative to the GFP-PM marker. Intensity plots show wildtype (WT) nephrin is well distributed across all regions of the cytosol, while A419T and C623F mutants appear to aggregate in the perinuclear region, with reduced (A419T) or near absent (C623F) expression at the PM (white arrows).