Notch signaling pathway in tooth shape variations

Abstract

Evolutionary changes in vertebrates are linked to genetic alterations that often affect tooth-crown shape, which is a criterion of speciation events. The Notch pathway is highly conserved between species and controls morphogenetic processes in most developing organs, including teeth. Epithelial loss of the Notch-ligand Jagged1 in developing mouse molars affects the location, size and interconnections of their cusps that lead to minor tooth-crown shape modifications convergent to those observed along Muridae evolution. These alterations are due to the modulation of numerous genes, where Notch signaling is a hub for essential morphogenetic networks. A three-dimensional metamorphosis approach allowed tooth morphology prediction in individuals carrying Jagged1 mutations. These results shed new light on Notch/Jagged1-mediated signaling as one of the crucial components for dental variations in evolution. Significance statementDental microevolution changes in vertebrates are regulated by the Notch signaling pathway.