Klotho (KL)

May have weak glycosidase activity towards glucuronylated steroids. However, it lacks essential active site Glu residues at positions 239 and 872, suggesting it may be dormant as a glycosidase in vivo.

May be involved in the regulation of calcium and phosphorus homeostasis by inhibiting the synthesis of vitamin D (By similarity). Essential element for the particular interaction between FGF23 and FGFR1 (By similarity).