Calcium Channel Regulation by Klotho

Science's STKE  25 Oct 2005:
Vol. 2005, Issue 307, pp. tw377
DOI: 10.1126/stke.3072005tw377

Klotho, a membrane protein with β-glucuronidase activity, also occurs in a soluble form that has recently been implicated as a hormone that regulates longevity in mice. Chang et al. now show that its enzymatic activity is required to activate the Ca2+ channel, TRPV5. Upon cleavage of sugar residues on TRPV5 by klotho, the channel becomes activated and accumulates at the surface of cells, increasing the influx of Ca2+. This interaction may control Ca2+ homeostasis in tissues such as the kidney, where both proteins are abundantly expressed in the mouse.

Q. Chang, S. Hoefs, A. W. van der Kemp, C. N. Topala, R. J. Bindels, J. G. Hoenderop, The β-glucuronidase klotho hydrolyzes and activates the TRPV5 channel. Science 310, 490-493 (2005). [Abstract] [Full Text]