Journal: Kidney international
Article Title: Proteomic analysis of the slit diaphragm complex: CLIC5 is a protein critical for podocyte morphology and function
doi: 10.1038/ki.2010.212
Figure Lengend Snippet: (a) Glomeruli were isolated from CLIC5+/+ and CLIC5−/− kidneys, detergent extracts were produced from them, and CLIC5 was immunoprecipitated. Immunoblotting of podocalyxin (top panel), pERM (second panel), and total ERM (third panel) showed coimmunoprecipitation of CLIC5 with these proteins. Blots were reprobed with anti-CLIC5 to confirm immunoprecipitation of CLIC5 (fourth and fifth panels). Immunoblotting of supernatants with actin controlled for equal amounts of lysates analyzed, and immunoblotting the supernatants for podocalyxin, pERM, and ERM confirmed their presence in extracts from CLIC5+/+ and CLIC5−/− glomeruli. (b) Images of mouse whole glomeruli fixed and labeled with CLIC5 (A and D, red), pERM (B, green), podocalyxin (E, green), and merged images (C and F). (C) The pERM-CLIC5 merged image shows colocalization of these proteins that appeared as yellow labeling in the podocyte processes (magnified inset). Colocalization of CLIC5 with podocalyxin was also noted as yellow labeling in the merged image (F). Fluorescence confocal images were taken at × 60 magnification. (c) Primary podocyte cultures from CLIC5+/+ (A–C and G–I) and CLIC5−/− (D–F and J–L) mice were grown for 14 days in vitro before they were fluorescently labeled with CLIC5 (A, D, G, and J, red), pERM (B and E, green), podocin (H and K, green), and phalloidin-labeled actin filaments (blue); merged images (C, F, I, and L). CLIC5 labeling was only detected in CLIC5+/+ podocytes and was absent from CLIC5−/− podocytes. The merged image (C) indicated that CLIC5 colocalized with pERM and was most evident near edges and cell-cell contact regions of the podocytes. The merged image of CLIC5 with podocin (I) showed no colocalization.
Article Snippet: The primary antibodies used were as follows: goat polyclonal anti-nephrin and goat polyclonal anti-podocalyxin (R&D Systems, Minneapolis, MN, USA); goat polyclonal anti-CLIC5 (Santa Cruz Biotechnology, Santa Cruz, CA, USA); rabbit polyclonal anti-CLIC5 and anti-transferrin receptor (Sigma, Saint Louis, MO, USA); anti-COX IV, anti-PSMA2, rabbit polyclonal anti-ERM, rabbit polyclonal anti-pERM and anti-flotillin 1 (Cell Signaling Technology, Danvers, MA, USA); rabbit polyclonal anti-podocin (Sigma); and goat anti-actin and rabbit anti-WT1 (Santa Cruz).
Techniques: Isolation, Produced, Immunoprecipitation, Western Blot, Labeling, Fluorescence, In Vitro