Rethinking autophagy during odontogenesis through autophagic flux

Tooth development requires precise coordination of proliferation, differentiation, and tissue remodeling. Although macroautophagy/autophagy has been implicated in odontogenesis, its dynamic regulation during embryonic tooth development remains poorly understood because previous studies relied primarily on static markers. In our recent study, we analyzed autophagic flux in mouse tooth germs using a tandem fluorescent reporter of microtubule associated protein 1 light chain 3 (LC3) combined with lysosomal associated membrane protein 1 (LAMP1) immunostaining and found that gestational protein restriction altered the autophagic vesicle profile in a stage- and compartment-specific manner. The most pronounced alterations occurred at the bud stage and coincided with reduced cell proliferation and increased apoptosis. These findings suggest that early odontogenesis is a particularly vulnerable window in which efficient and properly timed autophagic flux may be required for morphogenesis. Because tandem reporters cannot distinguish canonical autophagy from non-degradative LC3-dependent pathways, we also discuss this limitation and raise new questions about the role of autophagy in epithelial-mesenchymal interactions.