Matrix extracellular phosphoglycoprotein (MEPE)

Matrix extracellular phosphoglycoprotein (MEPE) is a secreted calcium-binding phosphoprotein belonging to the SIBLING family and functioning as a key regulator of bone and dentin mineralization, as well as systemic phosphate homeostasis[1][2][3]. The protein contains an ASARM motif, whose proteolytic cleavage produces peptides that potently inhibit mineralization by preventing hydroxyapatite formation, contributing to disorders such as hypophosphatemia and osteomalacia when abnormally expressed or processed[1][2]. MEPE is predominantly expressed by osteocytes in bone and also detected in odontoblasts, dental papilla cells, and some non-mineralizing tissues. It modulates osteoblast and osteoclast activity, restrains bone turnover, and interacts closely with other mineralization regulators, including PHEX, FGF23, and DMP1[1][2]. Genetic alterations or dysregulation of MEPE play significant roles in certain phosphate-wasting and bone-density diseases, and its levels in serum may serve as a biomarker for diagnosing or monitoring these conditions[1][2][3]. There is currently no evidence for direct therapeutic targeting of MEPE by approved drugs.

Other names

Osteoblast/osteocyte factor 45OsteoregulinOF45Matrix extracellular phosphoglycoprotein with ASARM motif (bone)MEPE