Amelogenesis: Transformation of a protein-mineral matrix into tooth enamel.
Amelogenesis: Transformation of a protein-mineral matrix into tooth enamel.
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DOI：
10.1016/j.jsb.2021.107809
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发表时间：
2021-12
影响因子：
3
通讯作者：
Diekwisch TGH
中科院分区：
文献类型：
--
作者：
Pandya M;Diekwisch TGH
在牙釉质形成过程中，有机牙釉质蛋白基质与磷酸钙矿物质相互作用，形成细长、平行和成束的牙釉质磷灰石晶体，具有非凡的硬度和生物力学弹性。牙釉质蛋白基质由独特的牙釉质蛋白组成，例如牙釉质蛋白、成釉细胞蛋白和牙釉质蛋白，它们由称为成釉细胞的高度专业化细胞分泌。成釉细胞还促进钙和磷酸根离子向牙釉质层的运输。在成釉细胞内，牙釉质蛋白作为具有 5 nm 亚基的多边形基质在分泌囊泡中运输。从成釉细胞排出后，牙釉质蛋白基质被重新组织成 20 nm 的亚基区室。牙釉质基质亚基区室的组装和扩张与 MMP20 牙釉质蛋白酶的 C 端裂解和 N 端釉原蛋白自组装相一致。当牙釉质晶体沉淀时，牙釉质蛋白相被重新配置以包围伸长的牙釉质晶体并促进它们在C轴方向上的伸长。在这个发育阶段，在牙釉蛋白进一步裂解后，牙釉蛋白分子的中心片段和富含聚脯氨酸的片段通过称为“脱落”的过程与生长的矿物晶体结合，而六方磷灰石晶体在纵向融合。牙釉质蛋白鞘包覆的牙釉质“dahlite”晶体不断伸长，直至形成致密的平行磷灰石晶体束，同时牙釉质基质不断被蛋白水解酶降解。总之，这些见解将牙釉质矿物成核和生长描述为牙釉质蛋白质和矿物离子之间复杂而动态的相互作用，促进定期接种的磷灰石生长和平行的牙釉质晶体伸长。
During enamel formation, the organic enamel protein matrix interacts with calcium phosphate minerals to form elongated, parallel, and bundled enamel apatite crystals of extraordinary hardness and biomechanical resilience. The enamel protein matrix consists of unique enamel proteins such as amelogenin, ameloblastin, and enamelin, which are secreted by highly specialized cells called ameloblasts. The ameloblasts also facilitate calcium and phosphate ion transport toward the enamel layer. Within ameloblasts, enamel proteins are transported as a polygonal matrix with 5nm subunits in secretory vesicles. Upon expulsion from the ameloblasts, the enamel protein matrix is re-organized into 20nm subunit compartments. Enamel matrix subunit compartment assembly and expansion coincide with C-terminal cleavage by the MMP20 enamel protease and N-terminal amelogenin self-assembly. Upon enamel crystal precipitation, the enamel protein phase is reconfigured to surround the elongating enamel crystals and facilitate their elongation in C-axis direction. At this stage of development, and upon further amelogenin cleavage, central and polyproline-rich fragments of the amelogenin molecule associate with the growing mineral crystals through a process termed “shedding”, while hexagonal apatite crystals fuse in longitudinal direction. Enamel protein sheath-coated enamel “dahlite” crystals continue to elongate until a dense bundle of parallel apatite crystals is formed, while the enamel matrix is continuously degraded by proteolytic enzymes. Together, these insights portrait enamel mineral nucleation and growth as a complex and dynamic set of interactions between enamel proteins and mineral ions that facilitate regularly seeded apatite growth and parallel enamel crystal elongation.
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影响因子：
4.6
作者：
Carneiro KM;Zhai H;Zhu L;Horst JA;Sitlin M;Nguyen M;Wagner M;Simpliciano C;Milder M;Chen CL;Ashby P;Bonde J;Li W;Habelitz S
通讯作者：
Habelitz S
影响因子：
9.8
作者：
Jin T;Ito Y;Luan X;Dangaria S;Walker C;Allen M;Kulkarni A;Gibson C;Braatz R;Liao X;Diekwisch TG
通讯作者：
Diekwisch TG
影响因子：
3.6
作者：
DIEKWISCH, TGH;BERMAN, BJ;SLAVKIN, HC
通讯作者：
SLAVKIN, HC
影响因子：
4.8
作者：
Bromley, Keith M.;Kiss, Andrew S.;Moradian-Oldak, Janet
通讯作者：
Moradian-Oldak, Janet
影响因子：
3
作者：
FINCHAM, AG;HU, Y;SNEAD, ML
通讯作者：
SNEAD, ML