Summary of key findings
Studies by Garg et al. and Ashworth et al. investigated the functional relevance of a key regulatory protein, cofilin-1, for podocyte actin dynamics (Ashworth et al. in PLos One 5:e12626, 2010; Garg et al. in J Biol Chem 285:22676–22688, 2010). Using different model organisms (zebrafish or transgenic mice), both groups observed a collapse of the glomerular filtration barrier upon inactivation of cofilin-1. In elegant biochemical studies, Garg et al. established that cofilin-1 activity is regulated by nephrin, which is part of the slit diaphragm complex. Two feedback loops stabilize cofilin-1 in the phosphorylated versus dephosphorylated state. The novel findings render cofilin-1 activity as potential diagnostic marker for pathological changes in the podocyte cytoarchitecture.
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Acknowledgments
M. J. M is supported by TP17 SFB/Transregio 57 of the German Research Foundation (DFG), the German Ministry for Science and Education (BMBF, 01 GN 0804), and a Boost Fund OPBo45 of the Excellence Initiative by the DFG (to MJM). We apologize for not having cited all relevant papers due to space limitations.
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Berger, K., Moeller, M.J. Cofilin-1 in the podocyte: a molecular switch for actin dynamics. Int Urol Nephrol 43, 273–275 (2011). https://doi.org/10.1007/s11255-010-9898-1
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DOI: https://doi.org/10.1007/s11255-010-9898-1