Lei Hai-hua, Liu He, Gao Xiang, Wen Jin-hua, Ge Li-hong
Peking University Stem Cell Research Center, Beijing 100081, China.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2008 Nov;43(11):675-9.
To investigate the occurrence of supernumerary upper incisor teeth in Pax6-/- mouse fetuses and to provide a model to explore the role of Pax6 in the upper incisor development and the mechanism of supernumerary teeth involving Pax6.
Twenty Pax6-/- mouse fetuses of strain DEBA were isolated on E18.5 (embryonic day). The fetuses were sectioned serially in coronal plane and stained with haematoxylin and erosion, then the presence of supernumerary teeth in the upper anterior area was examined histologically, and also the number, morphology and structure of lower incisor germs and the first and second molar germs in the maxilla and mandible were observed histologically. Eighteen E18.5 mouse fetuses of strain DEBA with Pax6+/+ genotype were used as control.
Of the 20 Pax6-/- fetuses examined, four possessed a single supernumerary tooth in the upper incisors' region. No supernumerary upper incisor teeth were observed in any of the 18 Pax6+/+ fetuses examined. In the regions of lower incisors and the first and second molars of the maxilla and mandible, no significant difference was observed between Pax6-/- and Pax6+/+ fetuses regarding the number, morphology and structure of tooth germs.
The results suggest that Pax6 played an important role in the development of upper incisor teeth in mice.
研究Pax6基因敲除小鼠胎儿中额外上切牙的发生情况，并提供一个模型来探索Pax6在上切牙发育中的作用以及涉及Pax6的多生牙机制。
在胚胎第18.5天（E18.5）分离出20只DEBA品系的Pax6基因敲除小鼠胎儿。将胎儿在冠状面连续切片，并用苏木精和伊红染色，然后组织学检查上前部区域是否存在额外牙，同时组织学观察下颌切牙胚以及上颌和下颌第一、二磨牙胚的数量、形态和结构。18只E18.5的DEBA品系Pax6基因野生型小鼠胎儿作为对照。
在检查的20只Pax6基因敲除胎儿中，4只在上切牙区域有一颗额外牙。在检查的18只Pax6基因野生型胎儿中均未观察到额外上切牙。在上下颌切牙以及第一、二磨牙区域中，Pax6基因敲除胎儿与Pax6基因野生型胎儿在牙胚数量、形态和结构方面未观察到显著差异。
结果表明Pax6在小鼠上切牙发育中起重要作用。
