The role of MOZ in normal and leukemic hematopoiesis

描述(由申请人提供) 分化的造血祖细胞显示出有序的成熟 染色质，这是一种进程，它提供了关于 细胞的身份和成熟阶段。这些核变化，在下面可见 光学显微镜，反映了造血基因表达的变化 干细胞在向各种成熟细胞分化的过程中经历 造血血统。然而，越来越明显的是， 染色质结构的变化不仅仅反映了分子的决定 转录因子的制备及其信号转导途径 请回答。相反，针对染色质重塑的改变有助于确定 基因表达的全球模式，可遗传的模式和 随着每个细胞周期的延长而增强。许多重要的造血调节剂都有 由于它们与白血病相关的染色体有关而被鉴定 易位。位于染色体8p11带的moz基因与此有关。 在三个独立的髓系白血病易位中。蚊子伙伴基因 被t(8；16)、t(8；22)和inv(8)破坏的分别是CREB结合 蛋白质(CBP)位于16p13，P300位于22q13，TIF2(NCoA-2)位于8q13； 合作伙伴是组蛋白乙酰转移酶和核受体共同调节因子。 MOZ是一个可能的组蛋白乙酰转移酶(HAT)，是组蛋白乙酰转移酶的创始成员 神秘的帽子家族，这个家族包括与细胞有关的蛋白质 周期调节、染色质重塑和剂量补偿。蚊子的 结构表明，像CBP/P300和其他帽子成员 在超家族中，Moz参与调节两者的蛋白质复合体 转录活性和染色质结构。这项提案考验着 假设MOZ是组蛋白乙酰转移酶并转录 在造血过程中发挥重要作用的辅调节因子。中断 染色体易位导致的MOZ基因被认为是干扰 关键的造血信号通路，扰乱骨髓生成，以及 有助于急性髓系白血病的发展。的具体目标 这一建议是为了1)描述MoZ在胚胎中的表达 发育、造血和细胞周期的Northern印迹分析， 免疫印迹、原位杂交和免疫组织化学；2)评估 MOZ的协同调节功能，以及它对完整的 乙酰转移酶活性，使用瞬时和逆转录病毒介导的稳定 造血干细胞的基因转染法和微量注射法研究 非造血细胞；以及3)定义如何破坏正常功能 应用靶向技术研究MOZ对小鼠胚胎发育和造血的影响 蚊子基因的破坏。这个项目的长期目标是 了解MoZ如何促进承诺和终端差异化 在造血过程中。

DESCRIPTION (provided by applicant) Differentiating hematopoietic progenitors demonstrate an orderly maturation of chromatin, a progression that provides distinctive morphologic cues as to a cell's identity and stage of maturity. These nuclear changes, visible under the light microscope, mirror the changes in gene expression that hematopoietic stem cells undergo as they differentiate towards the various mature hematopoietic lineages. However, it is becoming increasingly clear that changes in chromatin structure do not merely reflect the molecular decision making of transcription factors and the signaling pathways to which they respond. Rather, changes directed at chromatin remodeling help to determine global patterns of gene expression, patterns which can be inherited and enhanced with each cell cycle. Many important hematopoietic regulators have been identified due to their involvement in leukemia-associated chromosomal translocations. The MOZ gene, situated at chromosomal band 8p1l, is involved in three independent myeloid leukemia translocations. MOZ partner genes disrupted by t(8;16), t(8;22), and inv(8) are, respectively, the CREB binding protein (CBP) at 16p13, P300 at 22q13, and TIF2 (NCoA-2) at 8q13; all three partners are histone acetyltransferases and nuclear receptor coregulators. MOZ is a putative histone acetyltransferase (HAT) and the founding member of the MYST family of HATs, a family that includes proteins involved in cell cycle regulation, chromatin remodeling, and dosage compensation. MOZ's structure suggests that, like CBP/P300 and other members of the HAT superfamily, MOZ participates in protein complexes that modulate both transcriptional activity and chromatin structure. This proposal tests the hypothesis that MOZ is a histone acetyltransferase and transcriptional coregulator that plays an important role during hematopoiesis. Disruption of the MOZ gene by chromosomal translocations is proposed to interfere with critical hematopoietic signaling pathways, disrupt myelopoiesis, and contribute to the development of acute myeloid leukemia. The specific aims of this proposal are to 1) characterize MOZ expression during embryonic development, hematopoiesis, and the cell cycle using northern blotting, western blotting, in situ hybridization, and immunohistochemistry; 2) assess MOZ's coregulatory functions, and its dependence on an intact acetyltransferase activity, using transient and retroviral-mediated stable transfection assays and microinjection studies in hematopoietic and non-hematopoietic cells; and 3) define how disruption of the normal functions of MOZ affects murine embryonic development and hematopoiesis using targeted disruption of the MOZ gene. The long term goal of this project is to understand how MOZ contributes to commitment and terminal differentiation during hematopoiesis.