Genomic and functional investigations of the transcriptional regulatory network of tooth enamel development

项目摘要/摘要 在美国，超过10%的婴儿出生时就有牙齿异常，包括牙齿发育不全、畸形、 和釉质发育不良(ED)。牙齿发育的研究对于理解这些先天缺陷至关重要。 对口腔疾病的研究以及开发新的治疗方法和治疗方法，从而对口腔健康产生影响。然而， 控制牙齿发育的转录和表观遗传机制还不是很清楚。长的- 学期目标是识别和表征作为牙齿重要调节因子的转录因子。 健康和疾病方面的发展。这项建议的目标是了解转录和 牙釉质发育的表观遗传调控机制及功能丧失原因 P63基因的突变会导致牙齿异常，包括ED。P63是外胚层的主要转录因子 发育和动态平衡，如p63突变个体的外胚层发育不良所证明的，通常 涉及艾德和其他牙齿畸形。然而，p63的主要异构体ΔNp63的作用以及 ΔNp63调控牙齿染色质和转录调控环境的机制 由于缺乏有针对性的遗传系统，发育完全未知。为了满足这一需求，一口井- 建立了定义的ΔNp63基因敲除小鼠模型，以执行ΔNp63在 发育中的釉质器官。根据初步数据和其他人发表的作品的重新分析，它是 假设P63通过全面激活作为牙釉质发育的主要调节因子发挥作用 它的靶基因，对于驱动早期的细胞命运指定和后来的细胞分化事件是必不可少的 在釉质器官细胞中。利用基因组学和表观基因组学方法和新开发的小鼠模型 外胚层发育不良中的ED，其中ΔNp63基因敲除是在牙齿发育过程中诱导的，三个重要的 问题将会得到解答。目标1将定义在以下过程中需要p63行动的发育机制 牙齿发育。目标2将确定p63引导牙齿发育的分子机制。最后， 目标3将确定细胞-状态转换动力学和潜在的表观遗传机制，由 ΔNp63在牙齿发育中的作用总而言之，这些实验将定义 在广泛和动态的范围内管理牙釉质的发育，这将提供基础信息 对于开发更好的诊断、治疗和预防先天性和获得性牙病的方法至关重要。

Project Summary/Abstract In the U.S., more than 10% of infants are born with dental anomalies, including tooth agenesis, malformation, and enamel dysplasia (ED). The study of tooth development is critical for understanding these congenital disorders and developing novel therapies and treatments, and thus has implications for oral health. However, the transcriptional and epigenetic mechanisms that control tooth development is not well understood. The long- term goal is to identify and characterize the transcription factors that function as important regulators of tooth development in health and disease. The objective of this proposal is to understand the transcriptional and epigenetic regulatory mechanisms underlying tooth enamel development and to address why loss-of-function mutations of the p63 gene cause tooth anomalies, including ED. p63 is a master transcription factor of ectodermal development and homeostasis, as evidenced by ectodermal dysplasia in individuals with p63 mutations, often involving ED and other dental anomalies. However, the role of ΔNp63, the major isoform of p63, and the mechanisms by which ΔNp63 regulates the chromatin and transcriptional regulatory environment in tooth development is completely unknown due to lack of targeted genetic systems. In response to this need, a well- defined ΔNp63 knockout mouse model was generated to perform robust, inducible deletion of ΔNp63 in the developing enamel organ. Based on preliminary data and re-analysis of published work by others, it is hypothesized that p63 functions as a major regulator of tooth enamel development by comprehensively activating its target genes, which are essential for driving earlier cell fate specification and later cell differentiation events in the enamel organ cells. Using genomics and epigenomics approaches and a newly developed mouse model of ED in ectodermal dysplasia, in which ΔNp63 knockout is induced during tooth development, three important questions will be addressed. Aim 1 will define the developmental mechanisms that require p63 action during tooth development. Aim 2 willdefine the molecular mechanisms by which p63 directs tooth development. Finally, Aim 3 will identify the cell-state transition dynamics and the underlying epigenetic mechanism governed by ΔNp63 in tooth development. Collectively, these experiments will define the fundamental mechanisms that govern tooth enamel development on a broad and dynamic scale, which will provide foundational information essential for developing better ways to diagnose, treat, and prevent congenital and acquired dental disorders.