Functional examination of H3K4 methyltransferases in myeloid neoplasia

表观遗传调控的紊乱与肿瘤发生有着深刻的联系。甲基化组蛋白尾部的酶，特别是那些参与三胸组和多梳组之间的对立，是表观遗传调控的核心，经常在许多cancer.We突变条件小鼠品系的所有六个组蛋白3赖氨酸4（H3 K4）三胸组甲基转移酶，并系统地研究它们在发育过程中的作用，在种系和成人。这六个包括主要的白血病发生因子MLL 1，其姐妹基因MLL 2和SETD 1B。在这里，我们提出的工作的基础上，我们最近的研究结果，无论是Setd 1b或Mll 2在成年小鼠的损失引起骨髓瘤。我们的研究结果，加上已知的MLL 1在维持造血干细胞（HSC）中的作用，以及最近人类癌症外显子组研究中MLL 3和MLL 4突变的突出性，提出了一个新的研究任务，以了解造血中的Trithorax组。此外，我们相信我们的工作将大大有助于并受益于与其他SPP 1463合作伙伴的相互作用，特别是那些致力于MLL 1，Polycomb-Group和DNA甲基化的合作伙伴。总体而言，可以获得对髓系中主要表观遗传调节因子的基本综合理解。 我们最近的数据表明，Setd 1b缺失在成年小鼠中产生骨髓增生性肿瘤与人类慢性粒单核细胞白血病（CMML）的功能，和Mll 2缺失产生轻度髓系恶性肿瘤。在这些初步数据的基础上，我们计划评估条件突变Setd 1b，Mll 2和双Setd 1b/Mll 2小鼠的HSC和造血祖细胞室。我们预测造血干细胞的内在缺陷，这将导致向髓系分化的倾斜，因此计划进行骨髓移植研究。为了深入了解造血缺陷的分子基础，我们将生成总mRNA表达谱，比较Setd 1b、Mll 2和双Setd 1b/Mll 2条件性敲除与对照HSC，并辅以来自HSC和祖细胞群体的H3 K4 me 3、-me 2和-me 1染色质免疫沉淀（ChIP）。我们将通过比较结构-功能分析来补充小鼠的工作，以解释Setd 1b固有的髓系转化潜力，使用BAC转基因在Setd 1a和Setd 1b之间进行外显子交换。通过比较Setd 1b和Mll 2，我们的目标是将髓系中H3 K4甲基转移酶作用的系统理解与Polycomb-Group和其他SPP 1463伙伴产生的DNA甲基化知识相结合。此外，我们提供了一个关于我们的重组工程，BAC转基因和通用蛋白质标记方法的研讨会。

Perturbations of epigenetic regulation are profoundly linked with tumorigenesis. The enzymes that methylate histone tails, particularly those involved in the opposition between Trithorax- and Polycomb-Groups, are central to epigenetic regulation and frequently mutated in many cancers.We have made conditional mouse lines for all six histone 3 lysine 4 (H3K4) Trithorax-Group methyltransferases and are systematically examining their roles during development, in the germline and in the adult. These six include the major leukemogenic factor MLL1, its sister gene MLL2, and SETD1B. Here we propose work based on our recent findings that loss of either Setd1b or Mll2 in adult mice provokes myeloid neoplasia. Our findings, together with the known role of Mll1 in the maintenance of hematopoietic stem cells (HSCs) and the prominence of MLL3 and MLL4 mutations in recent human cancer exome studies, raise a new imperative for studies to understand the Trithorax-Group in hematopoiesis. Furthermore, we believe that our work will strongly contribute to and benefit from interactions with other SPP1463 partners, particularly those working on MLL1, Polycomb-Group and DNA methylation. Overall, a substantially integrated understanding of the major epigenetic regulators in the myeloid lineage can be obtained. Our recent data indicate that Setd1b deletion in adult mice produces myeloproliferative neoplasia with features of human chronic myelomonocytic leukemia (CMML), and Mll2 deletion produces a mild myeloid malignancy. On the basis of these preliminary data, we plan to evaluate the HSC and hematopoietic progenitor compartments in conditionally mutated Setd1b, Mll2 and double Setd1b/Mll2 mice. We predict intrinsic defects in HSCs, which results in skewing of differentiation toward the myeloid lineage and therefore plan to perform bone marrow transplantation studies. To gain insight into the molecular basis of the hematopoietic defect, we will generate total mRNA expression profiles comparing Setd1b, Mll2 and double Setd1b/Mll2 conditional knockouts versus control HSCs, complemented by H3K4me3, -me2 and -me1 chromatin immunoprecipitations (ChIPs) from HSC and progenitor cell populations. We will complement the mouse work with comparative structure-function analyses to explain the inherent myeloid transformation potential of Setd1b using BAC transgenesis for exon swaps between Setd1a and Setd1b.By comparison of Setd1b and Mll2, we aim to integrate a systematic understanding of H3K4 methyltransferase action in the myeloid lineage with the Polycomb-Group and DNA methylation knowledge generated by other SPP1463 partners. Furthermore, we offer a workshop on our recombineering, BAC transgenic and generic protein tagging methodologies to this SPP.