Calcium Regulation and Oral Health

项目摘要/摘要 钙是一系列生物功能的关键调节剂，也是组成钙的关键元素 牙釉质。在成熟期，牙釉质对钙的需求随着牙釉质的增加而增加。 晶体在宽度和厚度上都会膨胀。钙必须到达形成牙釉质的层，但这个过程是如何进行的 对成釉细胞的调控知之甚少。目前牙釉质中钙离子转运的模型主要集中在 钙离子通过进入、转运和排出等步骤进行跨细胞转运。鉴于有几部作品报道了 在转运和挤出步骤中，只有有限的信息可用于钙进入机制 成釉细胞。在这项拨款提案中，我将重点放在进入步骤上，通过检查商店运营的钙离子通道的角色 释放激活的钙通道(CRAC)。CRAC通道是细胞内钙内流的重要机制 上皮细胞。除免疫外，还存在CRAC通道(STIM1，ORAI1)突变的患者 系统缺陷，伴有钙化程度低的釉质形成不全。我的目标是确定STIM1和Orai1如何 参与了钙离子内流，以及这一过程是如何调控的。PI最近的研究表明，STIM1，Orai1 以及钙信号转导的CCK和CCK抑制剂RCAN1被鉴定为 在成熟过程中显著上调。我用定量聚合酶链式反应、免疫印迹和免疫组织化学方法证实了这些结果。因此， CA2通过CRAC通道进入成釉细胞，这一过程如何调控对成釉细胞 健康牙釉质的开发。建议拨款申请所提供的证据将有助于更好地 了解取消CRAC功能的全身性影响。这也将有助于医生在 对CRAC基因突变患者的牙医就诊做出决定以防止 牙科问题

PROJECT SUMMARY/ABSTRACT Calcium is a key regulator of a broad range of biological functions and is also a key element in the composition of dental enamel. During the maturation stage of amelogenesis, Ca2+ requirements increase as enamel crystals expand in width and thickness. Calcium must reach the forming enamel layer but how this process is regulated in ameloblasts is poorly understood. The current model for Ca2+ transport in enamel focuses on the transcellular passage of Ca2+ via the entry, transit and extrusion steps. Whereas several works have reported on the transit and extrusion steps, only limited information is available for Ca2+ entry mechanisms into ameloblasts. In this grant proposal, I focus on the entry step by examining the role of the store-operated Ca2+ release-activated Ca2+ (CRAC) channels. CRAC channels comprise important Ca2+ influx mechanism in epithelial cells. Patients with mutations to CRAC channels (STIM1, ORAI1) present, in addition to immune system deficiencies, with hypocalcified amelogenesis imperfecta. My goal is to identify how Stim1 and Orai1 are involved in Ca2+ entry and how this process is regulated. Recent work by the PI indicates that Stim1, Orai1 as well as well as the Ca2+ signaling cholecystokinin (Cck) and the Cck inhibitor Rcan1 were identified as being significantly up-regulated in maturation. I have confirmed these results by qPCR, Western blot and IHC. Thus Ca2+ influx into ameloblasts via CRAC channels and how this process is regulated is important for the development of healthy enamel. Evidence contributed by the proposed grant application will help to better understand the systemic effects of CRAC function abrogation. This will also help medical practitioners in making decisions concerning dentist visits to patients with mutations to CRAC channels in order to prevent dental problems