Adaptor protein complex 2-mediated, clathrin-dependent endocytosis, and related gene activities, are a prominent feature during maturation stage amelogenesis.
Adaptor protein complex 2-mediated, clathrin-dependent endocytosis, and related gene activities, are a prominent feature during maturation stage amelogenesis.
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DOI：
10.1002/jbmr.1779
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发表时间：
2013-03
影响因子：
6.2
通讯作者：
Paine, Michael L.
中科院分区：
文献类型：
--
作者：
Lacruz, Rodrigo S.;Brookes, Steven J.;Wen, Xin;Jimenez, Jaime M.;Vikman, Susanna;Hu, Ping;White, Shane N.;Lyngstadaas, S. Petter;Okamoto, Curtis T.;Smith, Charles E.;Paine, Michael L.
在无淀粉发生过程中定义釉质基质去除的分子事件尚不清楚。早期的报道表明，接合蛋白（AP）参与成釉细胞介导的内吞作用。牙釉质的形成包括分泌和成熟阶段，在成熟阶段吸收功能增强。通过实时荧光定量PCR，我们发现在成熟阶段啮齿动物牙釉质器官细胞中网格蛋白和接头蛋白亚基的表达上调。AP-2是四种不同的接头蛋白复合物中上调最多的。免疫定位证实AP-2和网格蛋白存在于成釉细胞中，在顶端极有最强的反应性。这些数据表明，釉质细胞的吸收功能涉及AP-2介导的、依赖网格蛋白的内吞作用，因此暗示釉质基质蛋白碎片可能存在特定的膜结合受体。其他内吞相关基因产物的mRNA表达也在成熟过程中上调，包括：溶酶体相关膜蛋白1 （Lamp1）、分化簇63和68 （Cd63和Cd68）、atp酶、H+转运、溶酶体V0亚基D2 （Atp6v0d2）、atp酶、H+转运、溶酶体V1亚基B2 （Atp6v1b2）、氯离子通道、电压敏感7 （Clcn7）和组织蛋白酶K （Ctsk）。免疫组织学数据证实了成熟阶段成釉细胞中许多这些蛋白的表达。同时对cd63缺失小鼠的牙釉质进行了检测。尽管成熟过程中牙釉质器官中mRNA和蛋白的表达增加，但cd63缺失小鼠的牙釉质表现正常。这可能表明Cd63和相关基因产物（如Lamp1和Cd68）之间存在固有的功能冗余。经釉质基质蛋白复合物Emdogain®处理的成釉细胞样LS8细胞显示AP-2和网格蛋白亚基上调，进一步支持了釉质基质蛋白内吞的膜结合受体调节途径的存在。这些数据共同定义了成釉细胞在牙釉质成熟过程中去除牙釉质基质可能使用的内吞途径。
Molecular events defining enamel matrix removal during amelogenesis are poorly understood. Early reports have suggested that adaptor proteins (AP) participate in ameloblast-mediated endocytosis. Enamel formation involves the secretory and maturation stages, with an increase in resorptive function during the latter. Here, using real time PCR, we show that the expression of clathrin and adaptor protein subunits are up-regulated in maturation stage rodent enamel organ cells. AP-2 is the most up-regulated of the four distinct adaptor protein complexes. Immunolocalization confirms the presence of AP-2 and clathrin in ameloblasts with strongest reactivity at the apical pole. These data suggest that the resorptive functions of enamel cells involve AP-2 mediated, clathrin dependent endocytosis, thus implying the likelihood of a specific membrane-bound receptor(s) of enamel matrix protein debris. The mRNA expression of other endocytosis-related gene products is also up-regulated during maturation including: lysosomal-associated membrane protein 1 (Lamp1), cluster of differentiation 63 and 68 (Cd63 and Cd68), ATPase, H+ transporting, lysosomal V0 subunit D2 (Atp6v0d2), ATPase, H+ transporting, lysosomal V1 subunit B2 (Atp6v1b2), chloride channel, voltage-sensitive 7 (Clcn7) and cathepsin K (Ctsk). Immunohistological data confirms the expression of a number of these proteins in maturation stage ameloblasts. The enamel of Cd63-null mice was also examined. Despite increased mRNA and protein expression in the enamel organ during maturation, the enamel of Cd63-null mice appeared normal. This may suggest inherent functional redundancies between Cd63 and related gene products, such as Lamp1 and Cd68. Ameloblast-like LS8 cells treated with the enamel matrix protein complex Emdogain® showed up-regulation of AP-2 and clathrin subunits, further supporting the existence of a membrane-bound receptor regulated pathway for the endocytosis of enamel matrix proteins. These data together define an endocytotic pathway likely used by ameloblasts to remove the enamel matrix during enamel maturation.
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DOI：
10.1085/jgp.201110596
发表时间：
2011-04
期刊：
The Journal of general physiology
影响因子：
--
作者：
DiCiccio JE;Steinberg BE
通讯作者：
Steinberg BE
影响因子：
56.9
作者：
Dell'Angelica, EC;Klumperman, J;Bonifacino, JS
通讯作者：
Bonifacino, JS
影响因子：
4.8
作者：
Andrejewski, N;Punnonen, EL;Saftig, P
通讯作者：
Saftig, P
DOI：
10.1016/j.biocel.2004.02.007
发表时间：
2004-11-01
影响因子：
4
作者：
Aisen, P
通讯作者：
Aisen, P
影响因子：
4.7
作者：
Chen, Jiong;Yang, Hong Y.;Li, Ming Y.
通讯作者：
Li, Ming Y.