The crosstalk of DNA and lysine methyltransferases in ADPKD.

摘要 常染色体显性多囊肾病（ADPKD）是由两种基因之一的突变引起的， PKD 1或PKD 2，而它不能完全理解的限制遗传环境，特别是， 在具有相同基因突变但疾病严重程度不同的家族中。表观遗传调控作为一种关键的 细胞命运和存活的驱动因素甚至可以发生在基因相同的人类中，这可能是一种替代方案。 解释PKD相关改变的方法。因此，基因表达的表观遗传调节的作用 蛋白质在ADPKD中的功能应成为科学研究的重点。不过除了 组蛋白去乙酰化酶（HDAC），DNA和组蛋白甲基化的作用以及介导 ADPKD中的这些过程在很大程度上仍未被探索。PKD 1在基因体区域高甲基化， 其表达在ADPKD中下调。通过进行全基因组亚硫酸氢盐测序（WGBS） 分析，我们已经确定了全基因组异常的DNA甲基化签名在ADPKD肾脏 与正常肾脏相比，这表明DNA甲基化是关键机制之一， 潜在的囊肿形成在五种DNA甲基转移酶中，DNMT 1是唯一起作用的酶。 维持人类基因组中DNA甲基化模式。DNMT 1在Pkd 1突变肾细胞中上调， 上皮细胞和组织，暗示其在维持异常DNA甲基化特征中的作用。 在ADPKD基因组中。我们将探讨DNMT 1在调节肾囊肿中的作用和机制 目标1的进展。由于我们确定了DNMT 1和Smyd 2之间的相互作用，SET-1基因中的一个是Smyd 2。 含有组蛋白（赖氨酸）甲基转移酶的结构域，这表明Smyd 2可能参与DNMT 1 介导的DNA甲基化。我们将研究DNMT 1和Smyd 2在DNA调控中的相互作用 甲基化，并进一步阐明Smyd 2介导的调节膀胱生成的分子机制 在目标2中，其可以解决Smyd 2是否作为DNMT 1在特定基因上募集平台 甲基化，从而突出了以前未被认识到的两个关键表观遗传之间的直接联系， 抑制系统，并提供了一个可能的解释，为什么DNMT 1的上调在癌症和 PKD仅针对患者基因组中的特定基因，而不是所有基因。此外，我们将测试如果德- 肼苯哒嗪和Smyd 2抑制剂介导的DNMT 1介导的高甲基化DNA甲基化延迟囊肿 aim 3中的体内生长。这是第一项不仅将DNMT 1和DNA甲基化与ADPKD联系起来， 还将相应的DNMT 1和Smyd 2信号传导连接在一起，调节DNA甲基化， 基因表达。此外，这项研究将产生与以下方面治疗相关的信息： 具有出色的翻译潜力。

Abstract Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in one of two genes, PKD1 or PKD2, whereas it cannot be fully understood in terms of the constrained genetic setting, especially, in families with the same genetic mutations but variable disease severity. Epigenetic regulation as a critical driver of cell fate and survival can occur even in genetically identical humans, which may be an alternative means of explaining PKD-associated alterations. Thus, the roles of epigenetic modulation of gene expression and protein functions in ADPKD should become the focus of scientific investigation. However, in addition to histone deacetylases (HDACs), the roles of DNA and histone methylation and the enzymes that mediate these processes in ADPKD remain largely unexplored. PKD1 is hypermethylated in gene-body regions and its expression is downregulated in ADPKD. By performing whole-genome bisulfite sequencing (WGBS) analysis, we have identified the genome-wide abnormal DNA methylation signatures in ADPKD kidneys compared to those in normal kidneys, suggesting that DNA methylation is one of the key mechanisms underlying cystogenesis. Within the five DNA methyltransferases, DNMT1 is the only enzyme that functions to maintain the DNA methylation patterns in human genome. DNMT1 was upregulated in Pkd1 mutant renal epithelial cells and tissues, implying its role in the maintenance of the abnormal DNA methylation signatures in ADPKD genome. We will investigate the roles and mechanisms of DNMT1 in regulating renal cyst progression in aim 1. Since we identified an interaction between DNMT1 and Smyd2, one of the SET- domain-containing histone (lysine) methyltransferases, it suggested that Smyd2 may be involved in DNMT1 mediated DNA methylation. We will investigate the crosstalk of DNMT1 and Smyd2 in the regulation of DNA methylation and further delineate Smyd2-mediated molecular mechanisms in the regulation of cystogenesis in aim 2, which may address if Smyd2 serves as a recruitment platform for DNMT1 on specific gene methylation, thus highlighting a previously unrecognized direct connection between two key epigenetic repression systems and providing a possible explanation of why the upregulation of DNMT1 in cancer and PKD only targets specific genes but not all genes in patients’ genome. Furthermore, we will test if de- methylation of hypermethylated DNA mediated by DNMT1 with Hydralazine and Smyd2 inhibitor delays cyst growth in vivo in aim 3. This is the first study that not only links DNMT1 and DNA methylation to ADPKD but also links the corresponding DNMT1 and Smyd2 signaling together in regulation of DNA methylation and gene expression. In addition, this study will produce information that will be therapeutically relevant with excelling potential for translation.