DENTIN SIALOPHOSPHOPROTEIN (DSPP) DURING ODONTOGENESIS

描述：（改编自研究者摘要）目前很少 已知关于牙齿细胞外的组织特异性基因调控 基质蛋白在牙形成过程中的作用。本提案的目的是研究 控制牙本质过程的调节机制 唾液磷蛋白（DSPP）基因在牙齿形成过程中的表达， 获取其生物学功能的信息。DSPP是一个大型处理器 一种被特异性切割产生两种牙本质蛋白质的蛋白质 牙本质涎蛋白（DSP）和牙本质磷蛋白，也称为 磷酸蛋白（DPP）。原位杂交研究显示， 的DSPP。应用计划阐明控制的分子机制 DSPP在成牙本质细胞中的表达（增强子）和下调 成釉细胞中的表达（沉默子）。假设是组织和 DSPP的发育调节通过离散的 转录因子与其同源顺式元件的相互作用 启动子的特定区域，并且该蛋白质在 牙齿矿化为了检验这一假设，提出了四个具体目标： 1)为了确定5 '上游启动子区的DNA序列， 先前鉴定的小鼠和人类基因组克隆; 2）确定区域 的DSPP启动子，赋予潜在的组织特异性表达 DSPP基因使用新的永生化牙细胞系和体内使用 3）建立转基因敲入DSPP LacZ小鼠模型 研究天然DSPP的体内内源性表达模式， 启动子，同时允许在纯合空 DSPP动物;和4）使用免疫组织化学方法测定DSPP过表达的影响。 转基因小鼠模型。这些实验将提供所需的初步数据 以及DSPP启动子在人类基因中未来潜在应用的背景 治疗策略的许多牙本质和釉质遗传性疾病。 此外，一旦完全表征，DSPP启动子可用于其他基因工程。 获得有益的牙齿特异性表达的治疗应用 与盖髓方式相关的靶基因。

DESCRIPTION: (Adapted from the investigator's abstract) Currently very little is known regarding the tissue-specific gene regulation of tooth extracellular matrix proteins during odontogenesis. The purpose of this proposal is to study the regulatory mechanisms that control the process of dentine Sialophosphoprotein (DSPP) gene expression during tooth formation, while gaining information to its biological function. DSPP is a large processor protein that is specifically cleaved giving rise to two dentine proteins dentine sialoprotein (DSP) and dentine phosphoprotein also known as phosphophoryn (DPP). In situ hybridization studies show the restricted pattern of DSPP. The application plan to elucidate the molecular mechanism that control the expression of DSPP in the odontoblasts (enhancers) and down-regulate expression (silencers) in ameloblasts. The hypothesis is that tissue and developmental regulation of DSPP is regulated both up and down through discrete interactions of transcription factors with their cognate cis-elements in specific region of the promoter and that this protein has an important role in tooth mineralization. To test this hypothesis, four specific aims are proposed: 1) to determine the DNA sequences of the 5' upstream promoter region of previous identified mouse and human genomic clones; 2) to determine the region of the DSPP promoter that confers the potential tissue specific expression of DSPP gene using novel immortalized dental cell lines and in vivo using a transgenic approach; 3) to generate transgenic Knock-in DSPP LacZ mouse model to investigate the in vivo endogenous patterns of expression of native DSPP promoter, while allowing the functional role to be explored in homozygous null DSPP animals; and 4) to determine the effects of DSPP over-expression using trasgenic mouse model. These experiments will provide needed preliminary data and background for the future potential use of the DSPP promoter in human gene therapy strategy for the numerous dentine and enamel genetic diseases. Furthermore, once fully characterized, the DSPP promoter could be used in other therapeutic applications to derive tooth specific expression of beneficial target genes related to pulp capping modalities.