title: Ca2+transport and signalling in enamel cells.
abstract: Dental enamel is one of the most remarkable examples of matrix-mediated biomineralization. Enamel crystals form de novo in a rich extracellular environment in a stage-dependent manner producing complex microstructural patterns that are visually stunning. This process is orchestrated by specialized epithelial cells known as ameloblasts which themselves undergo striking morphological changes, switching function from a secretory role to a cell primarily engaged in ionic transport. Ameloblasts are supported by a host of cell types which combined represent the enamel organ. Fully mineralized enamel is the hardest tissue found in vertebrates owing its properties partly to the unique mixture of ionic species represented and their highly organized assembly in the crystal lattice. Among the main elements found in enamel, Ca2+is the most abundant ion, yet how ameloblasts modulate Ca2+dynamics remains poorly known. This review describes previously proposed models for passive and active Ca2+transport, the intracellular Ca2+buffering systems expressed in ameloblasts and provides an up-dated view of current models concerning Ca2+influx and extrusion mechanisms, where most of the recent advances have been made. We also advance a new model for Ca2+transport by the enamel organ.
authors: Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, USA.
authors: Meerim K
authors: MK
authors: Nurbaeva
authors: Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, USA.
authors: Miriam
authors: M
authors: Eckstein
authors: Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA.
authors: Stefan
authors: S
authors: Feske
authors: Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, USA.
authors: Rodrigo S
authors: RS
authors: Lacruz
mesh_terms: D000565:Ameloblasts / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D003743:Dental Enamel / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans
chemical_list: D002118:Calcium
keywords: calcium; calcium channel; calcium regulation; calcium signalling; calcium transport