Journal
NEPHRON EXPERIMENTAL NEPHROLOGY
Volume 114, Issue 3, Pages E93-E106Publisher
KARGER
DOI: 10.1159/000262317
Keywords
Glomerular podocytes; Rho-GTPases; Rac1
Categories
Funding
- Kidney Foundation of Canada
- Canadian Institute of Health Research
- Ministry of Education, Science, Culture and Sports of Japan
- Fonds de la Recherche en Sante du Quebec
Ask authors/readers for more resources
Background/Aims: The function of glomerular podocytes is closely associated with the actin cytoskeleton. In this study, we studied the role of the small Rho-GTPase, Rac1, in actin organization in podocytes. Methods: Conditionally immortalized mouse podocytes (MP) stably expressing nephrin or control plasmid were used. Results: In MP, Rac1 activity increased significantly at 1 week of differentiation. MP stably expressing nephrin showed Rac1 activity significantly higher and more sustained than vector-expressing control cells. Antibody-mediated cross-linking of nephrin also activated Rac1. Differentiated MP showed more distinct lamellipodia/cellular processes, as compared with undifferentiated cells, which was further augmented by nephrin expression. Transient transfection of constitutively active Rac1 markedly increased the number of lamellipodia/cellular processes in undifferentiated MP, while the Rac1 inhibitor caused actin cytoskeleton derangement in differentiating MP. In the rat model of puromycin aminonucleoside nephrosis, RhoA activity was increased at Day 7 (at the peak of proteinuria), while Rac1 activity increased significantly only at Day 14, when the recovery process had started. Conclusion: Rac1 is activated in differentiating MP and nephrin potentiates Rac1 activation. Rac1 likely contributes to lamellipodia formation in differentiating MP and may contribute to process formation in podocytes recovering from injuries. Copyright (C) 2009 S. Karger AG, Basel
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available