Figure 3.

Podocin localizes to the SD. Immunogold labeling shows the subcellular distribution of podocin (arrowheads) at the SD (arrows). (a and b) Cross sections of adult rat kidney. (c) A low-power magnification of a flat section. The gold particles are specifically located at the insertion site of the SD in the podocyte cell membrane (arrows in a), whereas no label can be detected in the glomerular basement membrane. b shows a high-power magnification of a. In c, the tangential section shows exclusive labeling of podocyte foot processes (arrowheads). Bars: a and c, 100 nm; b, 200 nm.