Characterization of sodium dependent phosphate transporter 2 signaling in hard tissue mineralization

项目摘要 骨骼的生长和动态平衡需要钙和无机磷。数百万美国人 患有骨矿化障碍，有必要了解控制Hard的过程 组织矿化。PI不仅与羟基磷灰石的形成有关，而且羟基磷灰石是骨骼的主要晶体。 抗压强度，还调节成骨细胞和软骨细胞的分化和功能。PIT-2(基因： Slc20a2)是矿化组织中钠依赖的PI转运蛋白的主要形式。我们的实验室是 第一个确定了它在调节骨骼发育和矿化方面的强大作用。淘汰赛 小鼠的PIT-2基因导致牙齿和骨骼矿化异常，成骨细胞减少为证据 数量、骨密度和体积，以及门牙发育和釉质形成受损。这件事的重点是 研究旨在进一步探索PIT-2在细胞和细胞外调控骨骼形成的过程中的作用。 牙本质形成和釉质形成。具体地说，目标1将确认我们的初步调查结果并将其扩展到 确定是否需要PIT-2来调节成牙本质细胞和成釉细胞的数量、分化和/或 矿化活性缺乏会导致牙本质形成和釉质形成受损。PIT-2在人类免疫系统中的作用 牙本质修复和三级牙本质形成也将使用磨牙损伤小鼠模型进行研究。以特定的目标 2，我们将以成骨细胞为例，明确Pit-2在矿化细胞中的作用机制。A PI PIT-2的运输和传感/信号功能将通过工程化的PIT-2运输缺陷进行剖析 变种人。我们希望这些研究能更好地了解PI如何影响硬组织的功能 形成细胞，为矿化患者开发新疗法奠定基础 疾病，如骨质疏松症和骨量减少。这个项目将在华盛顿大学进行， 生物工程系与口腔健康科学系在DDS-PhD培训中的合作 私家侦探。PI将发展批判性思维技能，学习最先进的细胞和分子技术，在 体内转基因小鼠模型和数据分析，这将为他的独立研究做好准备。最终，一个 华盛顿大学强大的指导团队、多学科协作努力和资源 通过这一奖项的支持将使受训人员为未来终身教职的学习做好准备 生物矿化过程。

Project Summary Growth and homeostasis of bones require calcium and inorganic phosphorus (Pi). With millions of Americans suffering from bone mineralization disorders, there exists a need for understanding processes governing hard tissue mineralization. Pi is implicated in not only forming hydroxyapatite, the main crystal giving bone its compressive strength, but also regulating osteoblast and chondrocyte differentiation and function. PiT-2 (gene: Slc20a2) is the major form of sodium-dependent Pi transporters in mineralized tissue. Our laboratory is one of the first to have identified its potent role in regulating skeleton development and mineralization. Knockout of the PiT-2 gene in mice resulted in tooth and bone mineralization abnormalities, as evidenced by reduced osteoblast numbers, bone density and volume, and impaired incisor development and amelogenesis. The focus of this research is to explore further the role of PiT-2 in cellular and extracellular processes governing skeletogenesis, dentinogenesis, and amelogenesis. Specifically, Aim 1 will confirm and extend our preliminary findings to determine whether PiT-2 is required for regulation of odontoblast and ameloblast numbers, differentiation, and/or mineralizing activity with deficiencies leading to impaired dentinogenesis and amelogenesis. A role of PiT-2 in dentin repair and tertiary dentin formation will also be studied using a molar injury mouse model. In Specific Aim 2, we will define the mechanisms of action of PiT-2 in mineralizing cells using osteoblasts as an example. A Pi transport and sensing/signaling function of PiT-2 will be dissected through engineered PiT-2 transport deficient mutants. We expect these studies to provide a better understanding of how Pi influences functions of hard tissue forming cells, serving as a basis to develop novel therapeutics for patients suffering from mineralization disorders, such as osteoporosis and osteopenia. This project will take place at the University of Washington with collaborations between the Departments of Bioengineering and Oral Health Sciences during DDS-PhD training of the PI. The PI will develop critical thinking skills, learn state-of-the-art cellular and molecular techniques, in vivo transgenic mouse models, and data analysis that will prepare him for independent research. Ultimately, a strong mentorship team, multidisciplinary collaborative effort, and resources at the University of Washington with support through this award will prepare the trainee for a future tenure-track faculty position to study biomineralization processes.