Klotho/Kl (KL) Antibody – Goat Polyclonal

This gene encodes a type-I membrane protein that is related to beta-glucosidases. Reduced production of this protein has been observed in patients with chronic renal failure (CRF), and this may be one of the factors underlying the degenerative processes (e.g., arteriosclerosis, osteoporosis, and skin atrophy) seen in CRF. Also, mutations within this protein have been associated with ageing and bone loss. [provided by RefSeq, Jul 2008]

Klotho: 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 inactive as a glycosidase in vivo. May be involved in the regulation of calcium and phosphorus homeostasis by inhibiting the synthesis of active vitamin D. Essential factor for the specific interaction between FGF23 and FGFR1. Defects in KL are a cause of hyperphosphatemic familial tumoral calcinosis (HFTC). A severe metabolic disorder that manifests with hyperphosphatemia and massive calcium deposits in the skin and subcutaneous tissues. Some patients manifest recurrent, transient, painful swellings of the long bones associated with the radiographic findings of periosteal reaction and cortical hyperostosis and absence of skin involvement. Belongs to the glycosyl hydrolase 1 family. Klotho subfamily. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 3.2.1.31; Hydrolase; Membrane protein, integral

Chromosomal Location of Human Ortholog: 13q12

Cellular Component: apical plasma membrane; extracellular region; extracellular space; integral to membrane; integral to plasma membrane; intracellular; plasma membrane

Molecular Function: 1-phosphatidylinositol-3-kinase activity; beta-glucosidase activity; beta-glucuronidase activity; fibroblast growth factor binding; fibroblast growth factor receptor binding; hormone activity; phosphatidylinositol-4,5-bisphosphate 3-kinase activity; Ras guanyl-nucleotide exchange factor activity; signal transducer activity; vitamin D binding

Biological Process: aging; calcium ion homeostasis; carbohydrate metabolic process; energy reserve metabolic process; fibroblast growth factor receptor signaling pathway; insulin receptor signaling pathway; MAPKKK cascade; phosphoinositide phosphorylation; phosphoinositide-mediated signaling; positive regulation of bone mineralization; positive regulation of GTPase activity; regulation of phosphoinositide 3-kinase cascade

Disease: Tumoral Calcinosis, Hyperphosphatemic, Familial