Fig. 4.

Ndst1^−/− podocytes do not attach and spread as efficiently on fibronectin compared with Ndst1^+/+ podocytes. The graphs show the results of the cell adhesion assay (A) and spread cell area measurements (B) for Ndst1^+/+ and Ndst1^−/− podocytes in culture. A: differences in adhesion of Ndst1^−/− podocytes on fibronectin at 1, 2, and 4 h. A significant difference was observed in Ndst1^−/− podocyte adhesion (white bars) to fibronectin at 1 (P = 0.014) and 2 (P = 0.0005) h after seeding compared with Ndst1^+/+ podocytes. A similar but not significant difference in adhesion was observed at 4 h after seeding between Ndst1^+/+ and Ndst1^−/− podocytes. B: results of spread cell area measures at T = 2 h after seeding between Ndst1^+/+ (white bars) and Ndst1^−/− (black bars) podocytes, the Ndst1^−/− cells showing a twofold difference (P = 0.0001) in area compared with Ndst1^+/+ cells. C and D: Ndst1^+/+ and Ndst1^−/− podocytes stained with Alexa 488 phalloidin to demonstrate differences in actin organization at 2 h after seeding. Prominent clusters of actin can be seen around the periphery of the Ndst1^+/+ cells (C) and some cells show the beginning of stress fiber formation. The Ndst1^−/− cells (D) show less spreading and fewer clusters of actin around their periphery, some still retaining a pattern of cortical actin staining. Final magnification in C and D: ×400, bar = 50 μm.