Mu Haibin, Liu Xin, Geng Shuoshuo, Su Dian, Chang Heran, Li Lili, Jin Han, Wang Xiumei, Li Ying, Zhang Bin, Xie Xiaohua
Department of Stomatology, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
Institute of Hard Tissue Development and Regeneration, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
Front Physiol. 2021 Aug 16;12:660644. doi: 10.3389/fphys.2021.660644. eCollection 2021.
The and expressed in root mesenchyme were essential for the patterning and cellular differentiation of tooth root. The role of the epithelium-derived Bmps in tooth root development, however, had not been reported. In this study, we found that the double abrogation of and from mouse epithelium caused short root anomaly (SRA). The ; ; mice exhibited a persistent Hertwig's Epithelial Root Sheath (HERS) with the reduced cell death, and the down-regulated BMP-Smad4 and Erk signaling pathways. Moreover, the expression in the HERS, the Shh-Gli1 signaling, and expression in the root mesenchyme of the ; ; mice were also decreased, indicating a disrupted epithelium- mesenchyme interaction between HERS and root mesenchyme. Such disruption suppressed the and expression in the root mesenchyme, indicating an impairment on the differentiation and maturation of root odontoblasts. The impaired differentiation and maturation of root odontoblasts could be rescued partially by transgenic . Therefore, although required in a low dosage and with a functional redundancy, the epithelial Bmp2 and Bmp4 were indispensable for the HERS degeneration, as well as the differentiation and maturation of root mesenchyme.
在牙根间充质中表达的[具体基因名称1]和[具体基因名称2]对于牙根的形态发生和细胞分化至关重要。然而，上皮来源的骨形态发生蛋白（Bmps）在牙根发育中的作用尚未见报道。在本研究中，我们发现从小鼠上皮中双重缺失[具体基因名称1]和[具体基因名称2]会导致短根异常（SRA）。[具体基因名称1]；[具体基因名称2]；[具体基因名称3]小鼠表现出持续存在的赫特维希上皮根鞘（HERS），细胞死亡减少，骨形态发生蛋白- Smad4和细胞外信号调节激酶（Erk）信号通路下调。此外，[具体基因名称1]；[具体基因名称2]；[具体基因名称3]小鼠的HERS中[具体基因名称4]表达、Shh - Gli1信号以及牙根间充质中的[具体基因名称5]表达也降低，表明HERS与牙根间充质之间的上皮-间充质相互作用受到破坏。这种破坏抑制了牙根间充质中[具体基因名称6]和[具体基因名称7]的表达，表明对根牙本质细胞的分化和成熟产生了损害。根牙本质细胞分化和成熟的损害可通过转基因[具体基因名称8]部分挽救。因此，尽管上皮Bmp2和Bmp4需要低剂量且存在功能冗余，但它们对于HERS退化以及牙根间充质的分化和成熟是不可或缺的。
