大鼠牙胚发育早期核心结合因子1表达的时空特异性

Space-time specificity of the expression of core-binding factor 1 in the early growth stage of rat tooth germ

目的:探讨采用成骨细胞特异性转录因子核心结合因子1cDNA探针对大鼠不同时期牙胚进行原位杂交实验,以及其在牙胚发育过程中的表达。方法:实验于2003-05/08在北京军事医学科学院组织工程研究中心实验室完成。取SD孕期大鼠12只,利用核心结合因子1cDNA克隆产物,自行制备核心结合因子1cDNA探针,并对同笼后11d(蕾状期)、14d(帽状期)、17d(钟状早期)及出生后1d和9d(钟状晚期)4个时期的大鼠牙胚进行原位杂交实验,观察核心结合因子1在大鼠牙胚不同时期中的表达。结果:①大鼠牙胚蕾状期原位杂交可见明显阳性表达结果,其表达部位主要集中于牙胚及牙蕾顶部邻近的外胚间充质。②帽状期及钟状早期牙乳头、成牙本质细胞及成釉细胞均呈阳性表达。③钟状晚期表现于成牙本质细胞的表达明显下调,而成釉细胞呈阳性表达。结论:核心结合因子1在牙胚不同时期的表达有时空特异性,在大鼠牙胚发育早期即蕾状期的强阳性表达,表明核心结合因子1参与了牙胚的早期发育。

AIM： To explore the usage of osteoblast specific transcription factor corebinding factor α1 （cbfal） cDNA probe on tooth germs in rats by the way of in situ hybridization, and its expression in the growth process of tooth germ. METHODS： The experiment was done in the Laboratory of Structure Project Research Center of Academy of Military Medical Sciences from May to August 2003. Twelve SD pregnant rats were selected. Using corebinding factor 1 eDNA cloned product and made core-binding factor 1 eDNA probe by oneself. And in situ hybridization was performed in rat tooth germs of different four stages after in the same cage at the 11^th day （bud stage）, 14^th day （cap stage）, 17^th day （bell early stage） and postnatal 1 day and 9 day （bell late stage） to observe the expression of core-binding factor 1 in the different stages in rat tooth germs. RESULTS： ① There were significantly positive expressive results in situ hybridization in rat tooth germ bud stage. Its expressive parts concentrated mainly outside embryo mesenchyme around tooth germ and the top of tooth bud. ② The dental papolla, odontoblasts and ameloblast expressed all positive expression during cap stage and the early bell stage. ③ The expression of odontoblast significantly decreased in the late bell stage, while ameloblast showed positive expression. CONCLUSION： The expression of Cbfal in different stages in rat tooth germs had time and space specificity. The positive expression of the rat early stage tooth germ growth i.e., bud stage indicated that Cbfal took part in the early growth of tooth germ.