Regulator of phosphate homeostasis . Inhibits renal tubular phosphate transport by reducing SLC34A1 levels . Up-regulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism . Negatively regulates osteoblast differentiation and matrix mineralization .
Subcellular locations: Secreted
Secretion is dependent on O-glycosylation.
Expressed in osteogenic cells particularly during phases of active bone remodeling. In adult trabecular bone, expressed in osteocytes and flattened bone-lining cells (inactive osteoblasts).