Structure and Function of SET Domain Methyltransferases

SET结构域甲基转移酶的结构和功能

• 批准号: 7350235
• 负责人: RAYMOND C TRIEVEL
• 金额: $ 25.23万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7350235
• 关键词: Active Sites; Amino Acids; Binding; Binding Sites; Biochemical; Biochemistry; Biological Assay; Biological Process; Breast; Cell Cycle; Cell Cycle Checkpoint; Cell Division Process; Cell Nucleus; Cell division; Chemicals; Chromatin; Chromosomal Stability; Chromosome Segregation; Chromosomes; Colorectal; Complex; Cytokinesis; DNA Repair; DNA-Binding Proteins; Defect; Deletion Mutation; Development; Disruption; Enzymes; Gene Expression; Gene Expression Regulation; Gene Silencing; Genetic Transcription; Goals; Heterochromatin; Histone H3; Histone H4; Histone-Lysine N-Methyltransferase; Histones; Homologous Gene; Human; Kinetics; Knowledge; Laboratories; Lead; Libraries; Link; Lung; Lysine; Malignant Neoplasms; Malignant neoplasm of liver; Measures; Methylation; Methyltransferase; Mitosis; Mitotic; Modeling; Modification; Molecular Structure; Mono-S; Mutation; Nuclear; Nuclear Protein; Nuclear Proteins; Peptides; Plants; Play; Process; Property; Prostate; Proteins; Reaction; Reporting; Research; Research Personnel; Ribulose-Bisphosphate Carboxylase; Role; SET Domain; Scaffolding Protein; Site; Specificity; Structure; Substrate Specificity; TAF10 gene; TP53 gene; Techniques; Transcriptional Activation; Transcriptional Regulation; Variant; amino group; analog; cancer therapy; enzyme structure; enzyme substrate; inhibitor/antagonist; insight; leukemia; novel; programs; research study; structural biology; transcription factor

Histones are the major scaffolding proteins which organize and compact nuclear DMAin chromatin. These proteins undergo numerous types of chemical modifications that govern a variety of processes in the nucleus. Methylation of the amino acid lysine occurs in several histones and has been linked to the regulation of gene expression as well as in DNA repair processes and cell division. Histone lysine methyltransferases (HKMTs) are enzymes that catalyze the methylation of specific lysines within histones. HKMTs have been shown to function as both positive and negative regulators of gene expression, depending on the specific lysine that they methylate in histones. Recently, some HKMTs have been shown to methylate transcription factors (DNA binding proteins that activate gene expression), suggesting that these enzymes have broader roles in controlling transcription than previously believed. The importance of HKMTs in regulating gene expression is underscored by direct relationships between these enzymes and numerous forms of cancer. Deletions, mutations, or over-expression of several HKMTs have been linked malignancies such as leukemias and prostate, breast, lung, colorectal, and hepatic cancers. In order to gain insight into the functions of HKMTs in transcriptional regulation and how disruption of these enzymes can lead to cancer, we propose several experiments to characterize their protein substrate specificities and elucidate the chemical mechanism through which they methylate specific lysine residues in nuclear proteins. To achieve these goals, we will use a combination of biochemistry and structural biology in which we will determine the molecular structures of these enzymes bound to their protein substrates. Taken together, this research will provide not only novel insights into the functions of HKMTs in the nucleus, but will also provide avenues for the development of specific inhibitors against these enzymes in the treatment of cancer. Aim1: Determine the chemical mechanism of lysine methylation of HKMTs via biochemical and structural studies of a plant HKMT homolog known as Rubisco large subunit methyltransferase (LSMT). Aim2: Determine the substrate specificity of human SET7/9, a histone and transcription factor methyltransferase, through structural and biochemical techniques. Aim3: Determine the structure and substrate specificity of human SETS, an HKMT that is pivotal in regulating gene silencing and proper chromosome separation during cell division.

组蛋白是在染色质中组织和压实核DMA的主要支架蛋白。这些 蛋白质经历许多类型的化学修饰，这些化学修饰支配蛋白质中的各种过程。 原子核氨基酸赖氨酸的甲基化发生在几种组蛋白中，并已被链接到 调节基因表达以及DNA修复过程和细胞分裂。组蛋白赖氨酸 甲基转移酶（HKMT）是催化组蛋白内特定赖氨酸的甲基化的酶。 HKMT已被证明作为基因表达的正调节剂和负调节剂， 这取决于它们在组蛋白中甲基化的特定赖氨酸。最近，一些HKMT已经被证明 甲基化转录因子（激活基因表达的DNA结合蛋白），这表明， 这些酶在控制转录方面具有比以前认为的更广泛的作用。的重要性 HKMT在调节基因表达中的作用通过这些酶与 多种形式的癌症。几个HKMT的缺失、突变或过度表达已经被联系起来。 恶性肿瘤如白血病和前列腺癌、乳腺癌、肺癌、结肠直肠癌和肝癌。为了获得 深入了解HKMT在转录调控中的功能，以及这些酶的破坏如何 导致癌症，我们提出了几个实验来表征其蛋白质底物特异性， 阐明了它们甲基化核蛋白中特定赖氨酸残基的化学机制。 为了实现这些目标，我们将结合使用生物化学和结构生物学， 确定这些酶与其蛋白质底物结合的分子结构。总的来说，这 研究不仅将为HKMT在细胞核中的功能提供新的见解，而且还将提供 在癌症治疗中开发针对这些酶的特异性抑制剂的途径。 目的1：通过生物化学和结构分析确定HKMT赖氨酸甲基化的化学机制 植物HKMT同源物Rubisco大亚基甲基转移酶（LSMT）的研究。 目的2：确定人组蛋白和转录因子SET 7/9的底物特异性 甲基转移酶，通过结构和生物化学技术。 目的3：确定人SETS的结构和底物特异性，这是一种在调节 基因沉默和细胞分裂过程中染色体的适当分离。