Epigenetic and non-epigenetic role of SIRT1 in fluoride-induced cell stress

本申请的目的是表征表观遗传和非表观遗传功能， SIRT 1在氟斑牙适应性反应中的作用氟化物是有效的防龋剂 然而，长期过度暴露可导致氟斑牙。的30%以上 美国的儿童患有氟斑牙。我们的最终目标是开发新的策略 预防或减少氟斑牙，同时保持预防性公共用水的好处， 氟化以防止龋齿。最近，我们报道了氟化物激活SIRT 1和自噬， 作为一种适应性反应来保护细胞免受细胞应激。已知SIRT 1脱乙酰基 组蛋白抑制基因表达（表观遗传去乙酰化）。SIRT 1还可以使 非组蛋白蛋白（非表观遗传脱乙酰化）的数量， 自噬、线粒体代谢、细胞存活和生物体寿命。但具体 SIRT 1及其下游靶点在氟斑牙中的功能尚不清楚。我们的目标是 一项提案是确定SIRT 1如何在氟化物诱导的应激反应中发挥作用， 可以被调制的适当的目标，用于治疗牙齿 氟中毒我们的中心假设是SIRT 1可以通过启动自噬来发挥保护作用 和调节氟斑牙的表观遗传学。为了验证我们的假设，我们提出了三个具体的假设。 瞄准器AIM 1.氟化物作用下成釉细胞SIRT 1非组蛋白靶点的鉴定 体外AIM 2.在氟处理的成釉细胞中鉴定SIRT 1组蛋白靶点 体外AIM 3.确定SIRT 1过表达或条件性敲除是否影响釉质 体内发育和氟斑牙。为了实现这些目标，我们将使用SIRT 1 过表达和敲除成釉细胞样细胞LS 8（LS 8 Sirt 1/over和LS 8 Sirt 1/KO细胞） 通过CRISPR/Cas9技术在体外建立。我们将分析SIRT 1的作用， 体内SIRT 1过表达小鼠（SIRT 1 super）和条件性敲除小鼠（SIRT 1cKO）。 一旦揭示了表观遗传和非表观遗传SIRT 1在釉质病理生理学中的功能， 可能会开发新的策略来操纵SIRT 1功能， 预防氟斑牙。

The goal of this application is to characterize epigenetic and non-epigenetic functions of SIRT1 in adaptive responses during dental fluorosis. Fluoride is an effective caries prophylactic, however chronic over-exposure can result in dental fluorosis. More than 30% of children in the U.S. suffer from dental fluorosis. Our ultimate goal is to develop novel strategies that prevent or reduce dental fluorosis while keeping the benefit of prophylactic public water fluoridation to prevent caries. Recently we reported that fluoride activates SIRT1 and autophagy as an adaptive response to protect cells from cell stress. It is known that SIRT1 deacetylates histones to repress gene expression (epigenetic deacetylation). SIRT1 also deacetylates a number of non-histone proteins (non-epigenetic deacetylation) functioning in the regulation of autophagy, mitochondria metabolism, cell survival and organismal lifespan. However, the exact functions of SIRT1 and its downstream targets in dental fluorosis are unknown. Our goal in this proposal is to identify how SIRT1 functions in fluoride-induced stress responses and to find appropriate targets that could be modulated pharmacologically for the treatment of dental fluorosis. Our central hypothesis is that SIRT1 can play protective roles by intiating autophagy and regulating epigenetics in dental fluorosis. To test our hypothesis we propose three specific AIMs. AIM 1. Identify SIRT1 non-histone targets in ameloblast-derived cells treated with fluoride in vitro. AIM 2. Identify SIRT1 histone targets in ameloblast-derived cells treated with fluoride in vitro. AIM 3. Determine if SIRT1 over expression or conditional knockout effects enamel development and dental fluorosis in vivo. To attain these AIMs, we will use SIRT1 overexpressor and knockout ameloblast-like cells LS8 (LS8 Sirt1/over and LS8Sirt1/KO cells) established by the CRISPR/Cas9 technology in vitro. We will analyze the role of SIRT1 using SIRT1 over expressing mice (SIRT1super) and conditional knockout mice (SIRT1cKO) in vivo. Once epigenetic and non-epigenetic SIRT1 function in enamel pathophysiology is revealed, it may be possible to develop novel strategies to pharmacologically manipulate SIRT1 function to prevent dental fluorosis.