Fig. 2.

Immunofluorescence labeling for Ac-tub (red) in fetal rat kidney. Unlike adult kidneys, immunofluorescence intensity of Ac-tub signals is as low in the glomeruli as in the tubules. However, prominent Ac-tub signals like little pieces of thread (arrowheads) are frequently recognized between or on the immature columnar podocytes, whose apical membrane is labeled with anti-podocalyxin antibody (green). Similar signals of Ac-tub are also found in the lumen of immature tubules (arrows). These thread-like signals for Ac-tub presumably represent the primary cilia. a–a″ Late S-shaped body stage. b–b″ Capillary loop stage. Z-stacked images of 5 µm thickness. Bars 20 µm