Adam10-dependent Notch signaling establishes dental epithelial cell boundaries required for enamel formation

The Notch-mediated circuitry in the evolution and generation of new cell lineages: the tooth model

“…Previous studies in mammals have demonstrated that Notch signaling is essential for tooth development, morphology and tooth-specific mineral matrices deposition [ 36 , 37 , 39 , 40 , 42 , 48 , 51 , 106 ]. Notch signaling defines the four dental epithelial cell lineages through the temporo-spatial differential expression pattern of the various Notch receptors and ligands during odontogenesis [ 41 ] (Fig.…”

“…Enamel formation represents a very sophisticated cellular process, as it requires a tightly controlled sequence of cell proliferation, differentiation, extracellular matrix secretion and re-absorbance, and crystal mineralization [ 100 , 107 ]. This process needs to be tightly regulated spatially and temporally, as even minor changes can lead to functionally relevant alterations of the fine enamel structure [ 42 , 101 ]. In mammals, all four dental epithelial cell types of the enamel organ are indispensable for the formation of a properly structured and mineralized enamel [ 42 ].…”

“…This process needs to be tightly regulated spatially and temporally, as even minor changes can lead to functionally relevant alterations of the fine enamel structure [ 42 , 101 ]. In mammals, all four dental epithelial cell types of the enamel organ are indispensable for the formation of a properly structured and mineralized enamel [ 42 ]. Among these, ameloblasts are the most characterized and directly responsible for the secretion and maturation of the enamel matrix [ 41 , 100 ].…”

“…No studies described the expression of Notch ligands and receptors in other taxa such as reptiles or amphibians. In mice, mutations or inhibition of Notch signaling affects teeth and most specifically the formation and structure of enamel [ 36 , 37 , 42 , 48 , 51 ]. Constitutive deletion of Jagged2 is perinatally lethal in mice, and affects dental epithelial progenitor cells ability to form ameloblasts, leading to the development of teeth with abnormal morphology and lacking enamel [ 51 ].…”

“…Several studies have demonstrated that Notch signaling is involved in tooth morphology and enamel matrix deposition [ 35 – 42 ]. Teeth are organs that arise from progressive reciprocal inductive interactions between the stomodeum epithelium and the underlying neural crest-derived mesenchyme that transform the tooth primordia into complex mineralized structures with various cell types, among which the epithelial-derived ameloblasts that synthesize and secrete the organic components of the enamel [ 43 – 45 ].…”