The analysis of the network transcription regulation by the IKK・r in the tooth differentiation and development.

牙齿的发育受多种基因和细胞因子等生长因子的调控，牙齿的分化和形成有一个复杂的信号网络。然而，牙齿发育的所有机制的细节还不清楚。在本研究中，我们将IKK-y信号转导在牙齿发育的机制中进行了研究. IKK-γ mRNA在牙齿发育早期出现的证实从小鼠颌骨中取出各期牙胚及其周围组织进行培养。我们进行了IKK-γ的原位杂交，以证实IKK-γ在每个牙胚阶段的表达。结果表明，IKK-γ在牙胚发育的早期就有较强的表达.利用siRNA抑制IKK-γ的表达从小鼠颌骨中取出各期牙胚及其周围组织，进行器官培养。在器官培养过程中注射IKK-γ的siRNA，观察牙胚形成过程中的形态学变化。结果，siRNA不仅促进了牙胚的生长，而且促进了下颌骨的生长. IKK-γ siRNA组转录因子NF-κB的表达受到抑制。由于NF-κB在细胞分化、凋亡和病毒感染等过程中起着重要作用，因此有必要研究IKK-γ和NF-κB在牙齿发育过程中的细胞信号转导，提示IKK-γ与牙齿和颌骨的形成有关。提示IKK-γ是揭示牙齿发育和分化机制的重要信号。

The tooth development is adjusted by the appearance of various genes and growth factors such as cytokines, and a complex signal network is clarified to the differentiation and the formation of teeth. However, details of all mechanisms in the tooth development are not clarified. In this research, we forced the IKK-y signaling in the mechanism of the teeth development.1. Confirmation of mRNA appearance of IKK-γ in the early stage of teeth development The tooth germ of each stage and the surrounding tissue were removed from mouse's jaw bone and cultured. We did the in situ hybridization of IKK-γ in order to confirm the appearance of IKK-y expression in each tooth germ stage. As a result, it was confirmed that IKK-γ strongly appeared in the early stage of the tooth germ.2. Using siRNA to knock downs of IKK-γ expressionThe tooth germ of each stage and the surrounding tissue including the dental germ were removed from mouse's jawbone, and the organ culture was done. siRNA of IKK-γ was injected by the process of the organ culture, and a morphologic change in the formation of the tooth germ was examined. As a result, not only the growth of the tooth germ but also the growth of the lower jaw bone was spurred by the siRNA.3. Explore of the transcription factorsThe appearance of NF-κB that was one of the transcription factors was suppressed in the group of the siRNA of IKK-γ. As NF-κB plays a key role in cell differentiation, apoptosis and viral infection, it is necessity for examining the cell signaling of the activation of IKK-γ and NF-κB in the tooth development.Those results suggest that IKK-γ is associated with the formation of teeth and the jaw bones. Our data suggested that IKK-γ is an important signal to reveal the mechanism of the teeth development and the differentiation.