The importance of a potential phosphorylation site in enamelin on enamel formation

Abstract

Research in mice has provided new insight into the mechanisms through which the protein enamelin contributes to formation of tooth enamel. Enamelin is one of several proteins that make up the enamel matrix and is secreted from ameloblasts, the cells responsible for enamel formation. Previous work has shown that mutation of enamelin to prevent its phosphorylation at a specific site disrupts enamel formation. Xiaofang Wang from the Texas A&M University College of Dentistry, USA, and colleagues showed that the mutation caused a fragment of enamelin that is normally secreted to remain inside ameloblasts, altering the enamel matrix and affecting cellular processing of ameloblastin, another essential component of the enamel matrix. The finding shows that preventing phosphorylation of enamelin at the mutated site hinders interactions of the proteins required for enamel formation.

Keywords

ameloblastin / enamel / enamelin / FAM20C / phosphorylation / phosphoserine

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