Mechanisms Regulating DNA Methylation Maintenance in Chromatin

描述(由申请人提供)：DNA甲基化和组蛋白翻译后修饰(PTM)会对染色质模板化的生物过程产生影响，这些“表观遗传”标记在癌症中经常受到异常调控。因此，阐明控制DNA甲基化和组蛋白PTM的机制对于我们更好地理解表观遗传学在癌症中的作用是重要的。E3泛素连接酶uhrf1在基因上与维持细胞DNA甲基化有关，而uhrf1的失控与细胞的增殖、转移和对DNA损伤剂的超敏有关。这些最近uhrf1与DNA甲基化和癌症进展调控的联系表明，该蛋白可能是一个有利的治疗靶点。然而，uhrf1生物学的许多基本方面并不为人所知。因此，K99/R00建议的首要目标是促进我们对uhrf1与染色质的相互作用和DNA甲基化遗传调控的理解。我的初步研究证实，uhrf1串联Tudor结构域识别赖氨酸9上甲基化的组蛋白H3是其DNA甲基化维持功能所必需的。这项研究将以这些发现为基础：1)确定多价染色质参与如何驱动uhrf1的DNA甲基化维持功能；2)确定uhrf1对DNA甲基化维持的空间和时间贡献；3)定义uhrf1相互作用组；以及4)开发化学探针作为研究uhrf1功能的工具。这一建议得到了强有力的指导和培训计划的支持，为成功的独立研究生涯奠定了坚实的基础，该研究调查了表观遗传计划的调节及其功能障碍如何导致癌症的发生和发展。

DESCRIPTION (provided by applicant): DNA methylation and histone post-translational modifications (PTMs) elicit influence on chromatin-templated biological processes, and these 'epigenetic' marks are often aberrantly regulated in cancers. Elucidation of mechanisms controlling DNA methylation and histone PTMs are therefore important to better our understanding of the role of epigenetics in cancer. The E3 ubiquitin ligase UHRF1 is genetically linked to the maintenance of cellular DNA methylation and deregulation of UHRF1 correlates with cell proliferation, metastasis, and hypersensitivity to DNA damaging agents. These recent connections of UHRF1 to the regulation of DNA methylation and cancer progression suggest this protein may be a favorable therapeutic target. Yet, many fundamental aspects of UHRF1 biology are not known. The overarching goal of this K99/R00 proposal is therefore to advance our understanding of the interaction of UHRF1 with chromatin and the regulation of DNA methylation inheritance. My preliminary studies established that recognition of methylated histone H3 at lysine 9 by the UHRF1 tandem Tudor domain is required for its DNA methylation maintenance function. Studies in this proposal will build upon these findings to: 1) define how multivalent chromatin engagement drives the DNA methylation maintenance function of UHRF1, 2) determine the spatial and temporal contribution of UHRF1 to DNA methylation maintenance, 3) define the UHRF1 interactome, and 4) develop chemical probes as tools to study UHRF1 function. This proposal is supported by a strong mentorship and training plan, building a solid foundation for a successful independent research career investigating the regulation of the epigenetic program and how its dysfunction leads to the initiation and progression of cancer.