title: The epithelial calcium channel TRPV5 is regulated differentially by klotho and sialidase.
abstract: The transient receptor potential vanilloid type 5 (TRPV5) Ca(2+) channel facilitates transcellular Ca(2+) transport in the distal convoluted tubule (DCT) of the kidney. The channel is glycosylated with a complex type N-glycan and it has been postulated that hydrolysis of the terminal sialic acid(s) stimulate TRPV5 activity. The present study delineates the role of the N-glycan in TRPV5 activity using biochemical assays in Human Embryonic Kidney 293 cells expressing TRPV5, isoelectric focusing and total internal reflection fluorescent microscopy. The anti-aging hormone klotho and other glycosidases stimulate TRPV5-dependent Ca(2+) uptake. Klotho was found to increase the plasma membrane stability of TRPV5, via the TRPV5 N-glycan. Sialidase mimicked this stimulatory action. However, this effect was independent of the N-glycosylation state of TRPV5, since the N-glycosylation mutant (TRPV5(N358Q)) was activated to the same extent. We showed that the increased TRPV5 activity after sialidase treatment is caused by inhibition of lipid raft-mediated internalization. In addition, sialidase modified the N-glycan of transferrin, a model glycoprotein, differently from klotho. Previous studies showed that after klotho treatment, galectin-1 binds the TRPV5 N-glycan and thereby increases TRPV5 activity. However, galectin-3, but not galectin-1, was expressed in the DCT. Furthermore, an increase in TRPV5-mediated Ca(2+) uptake was detected after galectin-3 treatment. In conclusion, two distinct TRPV5 stimulatory mechanisms were demonstrated; a klotho-mediated effect that is dependent on the N-glycan of TRPV5 and a sialidase-mediated stimulation that is lipid raft-dependent and independent of the N-glycan of TRPV5.
authors: From the Department of Physiology and.
authors: Elizabeth H P
authors: EH
authors: Leunissen
authors: Anil V
authors: AV
authors: Nair
authors: Christian
authors: C
authors: Büll
authors: Dirk J
authors: DJ
authors: Lefeber
authors: Floris L
authors: FL
authors: van Delft
authors: René J M
authors: RJ
authors: Bindels
authors: Joost G J
authors: JG
authors: Hoenderop
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D037502:Galectin 3 / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D005966:Glucuronidase / Q000235:genetics / Q000494:pharmacology; D006026:Glycoside Hydrolases / Q000235:genetics / Q000494:pharmacology; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D000090265:Klotho Proteins; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D008856:Microscopy, Fluorescence; D009439:Neuraminidase / Q000235:genetics / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D011134:Polysaccharides / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D050916:TRPV Cation Channels / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D015220:Calcium Channels; D037502:Galectin 3; D011134:Polysaccharides; D011994:Recombinant Proteins; D050916:TRPV Cation Channels; C492239:TRPV5 protein, human; D049452:Green Fluorescent Proteins; D006026:Glycoside Hydrolases; D009439:Neuraminidase; D005966:Glucuronidase; D000090265:Klotho Proteins; D002118:Calcium
keywords: Calcium; Calcium Channels; Calcium Transport; Glycosylation; Membrane Trafficking; trpv5
references: ACS Chem Biol. 2010 Feb 19;5(2):163-76
references: 20020717
references: J Am Soc Nephrol. 2009 Aug;20(8):1693-704
references: 19423690
references: Biochim Biophys Acta. 2000 Jul 26;1475(3):321-8
references: 10913832
references: Nat Biotechnol. 2006 Apr;24(4):461-5
references: 16550175
references: J Biol Chem. 2004 Mar 12;279(11):9777-84
references: 14701853
references: Kidney Int. 1996 Sep;50(3):754-9
references: 8872948
references: Annu Rev Physiol. 2008;70:257-71
references: 17850211
references: FASEB J. 2002 Jul;16(9):983-92
references: 12087059
references: Nephrol Dial Transplant. 2008 Nov;23(11):3397-402
references: 18495742
references: Annu Rev Biochem. 2007;76:387-417
references: 17579562
references: EMBO J. 2003 Apr 1;22(7):1478-87
references: 12660155
references: Glycobiology. 2012 Jul;22(7):880-96
references: 22377912
references: J Am Soc Nephrol. 1997 Nov;8(11):1647-57
references: 9355067
references: Rev Physiol Biochem Pharmacol. 2007;158:77-160
references: 17729442
references: J Biol Chem. 1995 Mar 10;270(10):5198-206
references: 7890630
references: J Physiol. 2001 Dec 15;537(Pt 3):747-61
references: 11744752
references: Glycobiology. 2011 Nov;21(11):1416-25
references: 21673010
references: Physiology (Bethesda). 2008 Feb;23:32-40
references: 18268363
references: J Neurosci. 2002 Aug 15;22(16):7055-64
references: 12177202
references: Pflugers Arch. 2011 Aug;462(2):185-93
references: 21442474
references: FEBS Lett. 1985 Apr 8;183(1):65-9
references: 3979568
references: Nephrol Dial Transplant. 2004 Mar;19(3):602-7
references: 14767015
references: Biochim Biophys Acta. 2008 Mar;1780(3):520-4
references: 18036567
references: J Biol Chem. 2011 Feb 25;286(8):5935-41
references: 21173156
references: J Biol Chem. 1999 Mar 26;274(13):8375-8
references: 10085067
references: Cell Death Differ. 2012 Jan;19(1):170-9
references: 21681193
references: FASEB J. 2002 May;16(7):635-41
references: 11978727
references: Glycobiology. 2006 Apr;16(4):305-17
references: 16319083
references: Semin Cell Dev Biol. 2006 Dec;17(6):630-7
references: 17215147
references: Annu Rev Cell Dev Biol. 2010;26:285-314
references: 20929313
references: Am J Physiol Renal Physiol. 2000 Mar;278(3):F352-60
references: 10710538
references: J Am Soc Nephrol. 2011 Mar;22(3):508-17
references: 21164023
references: Traffic. 2010 Mar;11(3):348-60
references: 20051050
references: Proc Natl Acad Sci U S A. 2008 Jul 15;105(28):9805-10
references: 18606998
references: Electrophoresis. 1992 Jun;13(6):354-8
references: 1505496
references: Science. 2005 Oct 21;310(5747):490-3
references: 16239475
references: Am J Physiol Renal Physiol. 2006 Jul;291(1):F236-45
references: 16467129