Figure 5.

Loss of Vcl in podocytes results in the redistribution of adherens junction protein zonula occludens (ZO)-1 to the cytosol. Vinculin colocalizes with ZO-1 at cell–cell junctions (arrow) in wild-type mouse kidney tissue at age 8 weeks, and in primary podocytes (arrowheads) isolated from wild-type mice (a). Lipopolysaccharide (LPS) or protamine sulfate (PS) treatment in Pod-Vcl-KO podocytes results in an increase in cytosolic ZO-1, compared with control (Ctrl) podocytes. Arrowheads depict mislocalization of ZO-1 in Pod-Vcl-KO podocytes. Bar = 10 μm (b). Quantification of the distribution of ZO-1 by fluorescence intensity; n = 3; *P < 0.05; intensity was normalized to untreated conditions (c). Treatment with LPS or PS results in relocalization of ZO-1 to the cytosolic fraction in podocytes that lack vinculin (d). Quantification by densitometry of (d); n = 5; *P < 0.01 (e). Western blot of membrane and cytosolic fractions from podocytes isolated from Ctrl and Pod-Vcl-KO mice after treatment (in vivo) with LPS or NTS (f). Quantification by densitometry of (f); n = 5; *P < 0.01. Intensity was normalized to untreated conditions (g). C, cytoplasm; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; M, membrane; NTS, nephrotoxic serum. To optimize viewing of this image, please see the online version of this article at www.kidney-international.org.