TRPC6 is a glomerular slit diaphragm-associated channel required for normal renal function

Abstract

Progressive kidney failure is a genetically and clinically heterogeneous group of disorders. Podocyte foot processes and the interposed glomerular slit diaphragm are essential components of the permeability barrier in the kidney. Mutations in genes encoding structural proteins of the podocyte lead to the development of proteinuria, resulting in progressive kidney failure and focal segmental glomerulosclerosis. Here, we show that the canonical transient receptor potential 6 (TRPC6) ion channel is expressed in podocytes and is a component of the glomerular slit diaphragm. We identified five families with autosomal dominant focal segmental glomerulosclerosis in which disease segregated with mutations in the gene TRPC6 on chromosome 11q. Two of the TRPC6 mutants had increased current amplitudes. These data show that TRPC6 channel activity at the slit diaphragm is essential for proper regulation of podocyte structure and function.

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Figure 1: TRPC6 expression in the kidney glomerulus.
Figure 2: TRPC6 colocalizes and directly interacts with slit diaphragm proteins.
Figure 3: TRPC6 is upregulated in glomeruli of 2-d-old nephrin-deficient mice, as shown by fluorescence microscopy.
Figure 4: Pedigrees of families with inherited FSGS.
Figure 5: Electrophysiological analysis of mutant TRPC6 channels.

References

  1. 1

    Zandi-Nejad, K., Eddy, A.A., Glassock, R.J. & Brenner, B.M. Why is proteinuria an ominous biomarker of progressive kidney disease? Kidney Int. Suppl., S76–S89 (2004).

  2. 2

    Somlo, S. & Mundel, P. Getting a foothold in nephrotic syndrome. Nat. Genet. 24, 333–335 (2000).

    CAS  Article  Google Scholar 

  3. 3

    Pavenstadt, H., Kriz, W. & Kretzler, M. Cell biology of the glomerular podocyte. Physiol. Rev. 83, 253–307 (2003).

    CAS  Article  Google Scholar 

  4. 4

    Pollak, M.R. Inherited podocytopathies: FSGS and nephrotic syndrome from a genetic viewpoint. J. Am. Soc. Nephrol. 13, 3016–3023 (2002).

    Article  Google Scholar 

  5. 5

    Winn, M.P. et al. A mutation in the TRPC6 cation channel causes familial focal segmental glomerulosclerosis. Science, published online 5 May 2005 (10.1126/science.1106215).

  6. 6

    Montell, C. The TRP superfamily of cation channels. Sci. STKE 2005, re3 (2005).

    PubMed  Google Scholar 

  7. 7

    Clapham, D.E. TRP channels as cellular sensors. Nature 426, 517–524 (2003).

    CAS  Article  Google Scholar 

  8. 8

    Facemire, C.S., Mohler, P.J. & Arendshorst, W.J. Expression and relative abundance of short transient receptor potential channels in the rat renal microcirculation. Am. J. Physiol. Renal Physiol. 286, F546–F551 (2004).

    CAS  Article  Google Scholar 

  9. 9

    Mundel, P. et al. Synaptopodin: an actin-associated protein in telencephalic dendrites and renal podocytes. J. Cell Biol. 139, 193–204 (1997).

    CAS  Article  Google Scholar 

  10. 10

    Mundel, P. et al. Rearrangements of the cytoskeleton and cell contacts induce process formation during differentiation of conditionally immortalized mouse podocyte cell lines. Exp. Cell Res. 236, 248–258 (1997).

    CAS  Article  Google Scholar 

  11. 11

    Schnabel, E., Dekan, G., Miettinen, A. & Farquhar, M.G. Biogenesis of podocalyxin–the major glomerular sialoglycoprotein–in the newborn rat kidney. Eur. J. Cell Biol. 48, 313–326 (1989).

    CAS  PubMed  Google Scholar 

  12. 12

    Boute, N. et al. NPHS2, encoding the glomerular protein podocin, is mutated in autosomal recessive steroid-resistant nephrotic syndrome. Nat. Genet. 24, 349–354 (2000).

    CAS  Article  Google Scholar 

  13. 13

    Kestila, M. et al. Positionally cloned gene for a novel glomerular protein–nephrin–is mutated in congenital nephrotic syndrome. Mol. Cell 1, 575–582 (1998).

    CAS  Article  Google Scholar 

  14. 14

    Kim, J.M. et al. CD2-associated protein haploinsufficiency is linked to glomerular disease susceptibility. Science 300, 1298–1300 (2003).

    CAS  Article  Google Scholar 

  15. 15

    Reiser, J. et al. Induction of B7–1 in podocytes is associated with nephrotic syndrome. J. Clin. Invest. 113, 1390–1397 (2004).

    CAS  Article  Google Scholar 

  16. 16

    Putaala, H., Soininen, R., Kilpelainen, P., Wartiovaara, J. & Tryggvason, K. The murine nephrin gene is specifically expressed in kidney, brain and pancreas: inactivation of the gene leads to massive proteinuria and neonatal death. Hum. Mol. Genet. 10, 1–8 (2001).

    CAS  Article  Google Scholar 

  17. 17

    Hamano, Y. et al. Determinants of vascular permeability in the kidney glomerulus. J. Biol. Chem. 277, 31154–31162 (2002).

    CAS  Article  Google Scholar 

  18. 18

    Kaplan, J.M. et al. Mutations in ACTN4, encoding alpha-actinin-4, cause familial focal segmental glomerulosclerosis. Nat. Genet. 24, 251–256 (2000).

    CAS  Article  Google Scholar 

  19. 19

    Pavenstadt, H. & Bek, M. Podocyte electrophysiology, in vivo and in vitro. Microsc. Res. Tech. 57, 224–227 (2002).

    CAS  Article  Google Scholar 

  20. 20

    Drenckhahn, D. & Franke, R.P. Ultrastructural organization of contractile and cytoskeletal proteins in glomerular podocytes of chicken, rat, and man. Lab. Invest. 59, 673–682 (1988).

    CAS  PubMed  PubMed Central  Google Scholar 

  21. 21

    Huber, T.B. et al. Nephrin and CD2AP associate with phosphoinositide 3-OH kinase and stimulate AKT-dependent signaling. Mol. Cell. Biol. 23, 4917–4928 (2003).

    CAS  Article  Google Scholar 

  22. 22

    Verma, R. et al. Fyn binds to and phosphorylates the kidney slit diaphragm component Nephrin. J. Biol. Chem. 278, 20716–20723 (2003).

    CAS  Article  Google Scholar 

  23. 23

    Hisatsune, C. et al. Regulation of TRPC6 channel activity by tyrosine phosphorylation. J. Biol. Chem. 279, 18887–18894 (2004).

    CAS  Article  Google Scholar 

  24. 24

    Bandyopadhyay, B.C. et al. Apical localization of a functional TRPC3/TRPC6-Ca2+-signaling complex in polarized epithelial cells. Role in apical Ca2+ influx. J. Biol. Chem. 280, 12908–12916 (2005).

    CAS  Article  Google Scholar 

  25. 25

    Reiser, J., Kriz, W., Kretzler, M. & Mundel, P. The glomerular slit diaphragm is a modified adherens junction. J. Am. Soc. Nephrol. 11, 1–8 (2000).

    CAS  PubMed  Google Scholar 

  26. 26

    Notredame, C., Higgins, D.G. & Heringa, J. T-Coffee: A novel method for fast and accurate multiple sequence alignment. J. Mol. Biol. 302, 205–217 (2000).

    CAS  Article  Google Scholar 

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Acknowledgements

We thank the family members for their participation in these studies and M.A. Arnaout for discussions about the manuscript. This work was supported by grants from the US National Institutes of Health (M.R.P., P.M. and R.K.) as well as the Howard Hughes Medical Institute (P.L.S. and D.E.C.). J.R. was supported by the KMD Foundation and the KUFA-ASN Research Grant.

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Correspondence to Jochen Reiser or Martin R Pollak.

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Supplementary information

Supplementary Fig. 1

Summary of TRPC6 mutations. (PDF 99 kb)

Supplementary Table 1

Primer sequences. (PDF 43 kb)

Supplementary Note

Clinical information. (PDF 40 kb)

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Reiser, J., Polu, K., Möller, C. et al. TRPC6 is a glomerular slit diaphragm-associated channel required for normal renal function. Nat Genet 37, 739–744 (2005). https://doi.org/10.1038/ng1592

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