目的:成纤维细胞生长因子(FGFs)在整个牙齿开始和形态发生过程中,在介导牙齿上皮和间充质之间的相互作用中起关键作用。本研究旨在阐明FGF4和FGF10在牙齿发育调控中的作用。
方法:在本研究中,我们调查了FGF4和FGF10在小型猪的第三落叶磨牙(DM3)中的时空表达模式。早钟,和后期的钟声阶段。获得了怀孕的小型猪,并对样品进行组织学染色处理。非放射性原位杂交,免疫组织化学,实时荧光定量PCR检测FGF4和FGF10的mRNA和蛋白表达水平。
结果:FGF4在盖层阶段在牙齿上皮和间质中表达。在钟声早期,FGF4的上皮表达减少,而间充质表达增强。在钟声后期,FGF4的表达仅限于内釉质上皮(IEE)和分化的成牙本质细胞。在帽阶段,FGF10在上皮和间质中都强烈表达。在钟形早期,FGF10的表达集中在次生釉质结和周围的间质中。在钟形后期,在IEE中检测到FGF10较弱。
结论:我们的结果表明,FGF4和FGF10在调节上皮形态发生方面可能具有部分冗余功能。FGF4可能参与介导上皮和间充质之间相互作用的调节信号级联反应。此外,FGF10表达的下调可能与间充质细胞增殖的停止和成牙本质分化的启动有关.
OBJECTIVE: Fibroblast growth factors (FGFs) play pivotal roles in mediating interactions between dental epithelium and mesenchyme throughout tooth initiation and morphogenesis. This study aimed to elucidate the roles of FGF4 and FGF10 in the regulation of tooth development.
METHODS: In this study, we investigated spatiotemporal expression patterns of FGF4 and FGF10 in the third deciduous molars (DM3) of miniature pigs at the cap, early bell, and late bell stages. Pregnant miniature pigs were obtained, and the samples were processed for histological staining. Non-radioactive in situ hybridization, immunohistochemistry, and real-time PCR were used to detect mRNA and protein expression levels of FGF4 and FGF10.
RESULTS: FGF4 was expressed in the dental epithelium and mesenchyme at the cap stage. At the early bell stage, epithelial expression of FGF4 was reduced while mesenchymal expression got stronger. At the late bell stage, the FGF4 expression was restricted to the inner enamel epithelium (IEE) and differentiating odontoblasts. FGF10 was expressed intensely in both epithelium and mesenchyme at the cap stage. The expression of FGF10 was concentrated in the secondary enamel knots and surrounding mesenchyme at the early bell stage. FGF10 was weakly detected in the IEE by the late bell stage.
CONCLUSIONS: Our results indicated that FGF4 and FGF10 might have partially redundant functions in regulating epithelium morphogenesis. FGF4 may be involved in regulatory signaling cascades mediating interactions between the epithelium and mesenchyme. In addition, the downregulation of FGF10 expression may be associated with the cessation of mesenchymal cell proliferation and initiation of preodontoblast polarization.