They observed that ASARM
was abnormally produced in patients with familial rickets, and that both symptoms and ASARM
production could be attenuated by a diet high in vitamin D and phosphate during growth.
Part of the C terminal of MEPE is composed of ASARM (acidic, serine- and aspartic acid-rich motif), which binds avidly to hydroxyapatite when phosphorylated, preventing mineralization, in other words, the ASARM peptide is a minhibin, a factor which inhibits mineralization.
MEPE-ASARM peptides control extracellular matrix mineralization by binding to hydroxyapatite: An inhibition regulated by PHEX cleavage of ASARM.