Université de Fribourg

Arp3 controls the podocyte architecture at the kidney filtration barrier

Schell, Christoph ; Sabass, Benedikt ; Helmstaedter, Martin ; Geist, Felix ; Abed, Ahmed ; Yasuda-Yamahara, Mako ; Sigle, August ; Maier, Jasmin I. ; Grahammer, Florian ; Siegerist, Florian ; Artelt, Nadine ; Endlich, Nicole ; Kerjaschki, Dontscho ; Arnold, Hans-Henning ; Dengjel, Jörn ; Rogg, Manuel ; Huber, Tobias B.

In: Developmental Cell, 2018, vol. 47, no. 6, p. 741-757.e8

Podocytes, highly specialized epithelial cells, build the outer part of the kidney filtration barrier and withstand high mechanical forces through a complex network of cellular protrusions. Here, we show that Arp2/3-dependent actin polymerization controls actomyosin contractility and focal adhesion maturation of podocyte protrusions and thereby regulates formation, maintenance, and capacity...

Université de Fribourg

A multi-layered quantitative in vivo expression atlas of the podocyte unravels kidney disease candidate genes

Rinschen, Markus M. ; Gödel, Markus ; Grahammer, Florian ; Zschiedrich, Stefan ; Helmstädter, Martin ; Kretz, Oliver ; Zarei, Mostafa ; Braun, Daniela A. ; Dittrich, Sebastian ; Pahmeyer, Caroline ; Schroder, Patricia ; Teetzen, Carolin ; Gee, HeonYung ; Daouk, Ghaleb ; Pohl, Martin ; Kuhn, Elisa ; Schermer, Bernhard ; Küttner, Victoria ; Boerries, Melanie ; Busch, Hauke ; Schiffer, Mario ; Bergmann, Carsten ; Krüger, Marcus ; Hildebrandt, Friedhelm ; Dengjel, Jörn ; Benzing, Thomas ; Huber, Tobias B.

In: Cell Reports, 2018, vol. 23, no. 8, p. 2495–2508

Damage to and loss of glomerular podocytes has been identified as the culprit lesion in progressive kidney diseases. Here, we combine mass spectrometry-based proteomics with mRNA sequencing, bioinformatics, and hypothesis-driven studies to provide a comprehensive and quantitative map of mammalian podocytes that identifies unanticipated signaling pathways. Comparison of the in vivo datasets...

Université de Fribourg

The FERM protein EPB41L5 regulates actomyosin contractility and focal adhesion formation to maintain the kidney filtration barrier

Schell, Christoph ; Rogg, Manuel ; Suhm, Martina ; Helmstädter, Martin ; Sellung, Dominik ; Yasuda-Yamahara, Mako ; Kretz, Oliver ; Küttner, Victoria ; Suleiman, Hani ; Kollipara, Laxmikanth ; Zahedi, René P. ; Sickmann, Albert ; Eimer, Stefan ; Shaw, Andrey S. ; Kramer-Zucker, Albrecht ; Hirano-Kobayashi, Mariko ; Abe, Takaya ; Aizawa, Shinichi ; Grahammer, Florian ; Hartleben, Björn ; Dengjel, Jörn ; Huber, Tobias B.

In: Proceedings of the National Academy of Sciences, 2017, vol. 114, no. 23, p. E4621–E4630

Podocytes form the outer part of the glomerular filter, where they have to withstand enormous transcapillary filtration forces driving glomerular filtration. Detachment of podocytes from the glomerular basement membrane precedes most glomerular diseases. However, little is known about the regulation of podocyte adhesion in vivo. Thus, we systematically screened for podocyte-specific focal...

Université de Fribourg

MTOR regulates endocytosis and nutrient transport in proximal tubular cells

Grahammer, Florian ; Ramakrishnan, Suresh K. ; Rinschen, Markus M. ; Larionov, Alexey A. ; Syed, Maryam ; Khatib, Hazim ; Roerden, Malte ; Sass, Jörn Oliver ; Helmstaedter, Martin ; Osenberg, Dorothea ; Kühne, Lucas ; Kretz, Oliver ; Wanner, Nicola ; Jouret, Francois ; Benzing, Thomas ; Artunc, Ferruh ; Huber, Tobias B. ; Theilig, Franziska

In: Journal of the American Society of Nephrology, 2016, p. -

Renal proximal tubular cells constantly recycle nutrients to ensure minimal loss of vital substrates into the urine. Although most of the transport mechanisms have been discovered at the molecular level, little is known about the factors regulating these processes. Here, we show that mTORC1 and mTORC2 specifically and synergistically regulate PTC endocytosis and transport processes. Using a...