Kidney Glomerulus Tight Junctions. In the fetal glomerulus the tight junction forms between immature podocytes. Glomerular slit diaphragms and endothelial junctions express only one isoform of the tight junction protein zo 1.
We describe that in addition to the proximal tubule which has been recognized as the main site of accumulation and injury other segments of the nephron such as glomeruli vessels and distal nephron show also deleterious effects. In the adult glomerulus the tight junction gives way to a more specialized junction known as the slit diaphragm. When zo 1 was localized in differentiating glomeruli in the newborn rat kidney it was present early in development when the apical junctional complexes between presumptive podocytes are composed of typical tight and adhering junctions.
As a fence it generates and maintains the apicobasal polarity of cells that form the confluent epithelium.
Reiser j 1 kriz w kretzler m mundel p. However the functional role of the tj in the glomerular podocyte is unclear. Its distribution appeared to be continuous along the continuous slit membrane junction. In diabetic nephropathy the gene expression of claudins in particular claudin 1 is markedly upregulated.