THE STRUCTURAL BASIS FOR THE ASSEMBLY AND REGULATION OF THE MLL CORE COMPLEX

MLL 核心复合体组装和调节的结构基础

• 批准号: 7955578
• 负责人: Michael S. Cosgrove
• 金额: $ 1.19万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7955578
• 关键词: Acute leukemia; Amino Acids; Antineoplastic Agents; Binding; Binding Sites; Biological; Complex; Computer Retrieval of Information on Scientific Projects Database; DNA Sequence Rearrangement; Data; Development; Diabetes Mellitus; Epigenetic Process; Funding; Goals; Grant; Hematopoiesis; Histone H3; Homeobox Genes; Housing; Human; Institution; Insulin; Investigation; Lysine; MLL gene; Maps; Methylation; Molecular; Mono-S; Myeloid-Lymphoid Leukemia Protein; Oncogenic; Oral; Outcome; Peptides; Proteins; Regulation; Research; Research Personnel; Resolution; Resources; Role; SET Domain; Site; Solutions; Source; Specificity; Structural Protein; Structure; Testing; United States National Institutes of Health; Vitamin B 12; adduct; base; design; histone methyltransferase; leukemia; monomer; outcome forecast; protein complex; protein protein interaction

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The Mixed Lineage Leukemia (MLL) protein catalyzes histone H3 lysine 4 (H3K4) methylation, which is an epigenetic mark essential for the regulation of HOX genes in hematopoiesis and development. Translocations that disrupt the MLL gene are present in a unique group of acute leukemias, often predicting a poor prognosis. Other MLL rearrangements and amplifications increase MLL¿¿"s enzymatic activity and are oncogenic. MLL contains an evolutionarily conserved ~130 amino acid SET domain that catalyzes H3K4 methylation. Recent studies indicate that the enzymatic activity of MLL is regulated by a conserved complex of proteins including WDR5, RbBP5, and ASH2L. These proteins form an independent complex that binds to MLL and regulates MLL¿¿"s ability to mono-, di-, or trimethylate H3K4, a phenomenon known as ¿¿¿Product Specificity¿¿". Since different levels of methylation of H3K4 are associated with different transcriptional outcomes, it is imperative to understand the molecular mechanisms by which the product specificity of MLL is regulated. Despite the important biological role of MLL and its involvement in human leukemia, there is currently little information about the protein-structural features that are responsible for the enzymatic activity of MLL. The long-term goal of this research is to fully characterize the histone methyltransferase activity of MLL to facilitate the identification and rational design of new anti-cancer drugs for the treatment of human leukemias. This proposal takes a structure-function approach to investigate the molecular mechanisms of MLL SET domain regulation by protein-protein interactions. We have mapped the site of interaction between MLL and WDR5, and have obtained crystals of WDR5 with a peptide derived from MLL. The initial structure diffracted to 1.72 angstroms, and elucidtaed the peptide binding site. For this investigation, we would like to obtain higher resolution data with a longer peptide to determine if other interactions between MLL and WDR5 are important. For an unrelated project, we have also recently obtained crystals of an insulin-vitamin B12 adduct, which offers a potential oral alternative for insulin treatment for diabetes. While we have not tested them for diffraction yet (we don`t have an in house diffractometer), we have confirmed that the crystals are protein, and that the insulin B12 adduct forms monomers in solution.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以出现在其他 CRISP 条目中 列出的机构是。 中心，不一定是研究者的机构。 混合谱系白血病 (MLL) 蛋白催化组蛋白 H3 赖氨酸 4 (H3K4) 甲基化，这是调节造血和发育过程中 HOX 基因所必需的表观遗传标记。破坏 MLL 基因的易位存在于一组独特的急性白血病中。 ，通常预示着不良预后。其他 MLL 重排和扩增会增加 MLL¿ ¿ MLL 含有一个进化上保守的约 130 个氨基酸的 SET 结构域，可催化 H3K4 甲基化。最近的研究表明，MLL 的酶活性受到保守的蛋白质复合物（包括 WDR5、RbBP5 和 ASH2L）的调节。蛋白质形成独立的复合物，与 MLL 结合并调节 MLL 的单甲基化、二甲基化或三甲基化能力H3K4，一种称为 ¿ ¿ ¿产品特殊性¿ ¿由于 H3K4 甲基化的不同水平与不同的转录结果相关，因此有必要了解 MLL 产物特异性调节的分子机制。尽管 MLL 具有重要的生物学作用及其在人类白血病中的参与，但目前有关 MLL 酶活性的蛋白质结构特征的信息很少。本研究的长期目标是充分表征 MLL 的组蛋白甲基转移酶活性，以促进 MLL 的识别和合理设计。用于治疗人类白血病的新抗癌药物该提案采用结构-功能方法来研究通过蛋白质-蛋白质相互作用调节 MLL SET 结构域的分子机制，并绘制了 MLL 和 WDR5 之间相互作用的位点。获得了 WDR5 的晶体，其初始结构衍射至 1.72 埃，并阐明了肽结合位点。更长的肽来确定 MLL 和 WDR5 之间的其他相互作用是否重要 对于一个不相关的项目，我们最近还获得了胰岛素-维生素 B12 加合物的晶体，它为糖尿病的胰岛素治疗提供了潜在的口服替代品。尚未对它们进行衍射测试（我们没有内部衍射仪），我们已确认晶体是蛋白质，并且胰岛素 B12 加合物在溶液中形成单体。