Figure 1

Kif21a shows a specific expression during zebrafish development and localized to the glomerular filtration barrier. (A, B) Expression analysis of kif21a in zebrafish using semiquantitative reverse-transcription polymerase chain reaction (RT-PCR) on cDNA of different developmental embryonic stages (A) and adult organs (B). H₂O served as negative control and ef1α as loading control; Primer dimer (PD). The grouping of gel images cropped from different parts of the same gel image is delineated with white spaces. (C) Whole-mount in situ hybridization (WISH) analysis detecting temporal and spatial kif21a expression at different stages during zebrafish embryonic development (white arrow marks the optic stalk at 18 somite stage; black arrowheads mark the somites at 1 day post-fertilization (dpf); white circle depicts the glomerular area). (D) Glomerular sections of 5dpf old Tg(wt1b:GFP) zebrafish embryos (green) that were immunostained for Kif21a (magenta) and counterstained with DAPI (blue) as a nuclear marker. A respective immunostaining without the secondary antibody served as negative control. Scale bar represents 25 µm. (E) Representative electron micrograph showing immunogold-labelling of Kif21a (magenta arrows) in the glomerular region from 5dpf old zebrafish embryos. Green arrowheads point to podocyte foot processes and black arrows mark the glomerular basement membrane. Bowman’s space (BS), capillary lumen (CL), fenestrated endothelial cell (EC). Scale bar represents 250 nm. Unprocessed gel images for (A and B) are presented in Supplementary Fig. S2.