The Role of Mi2/NuRD Complex on the Expression of Human Gamma-Globin Gene

描述（由申请人提供）：认为MBD 2通过募集Mi2/NuRD阻遏物复合物在某些基因沉默中发挥作用。为了更好地研究Mi2/NuRD复合物如何在沉默？珠蛋白，我们已经着手在人类造血祖细胞中研究该模型。当在分化培养基上培养时，这些细胞模仿发育期间发生的血红蛋白转换。由于在携带人基因座的小鼠红系细胞上敲低Mi2的效果比敲低MBD 2大几倍，因此将研究Mi2以确定其是否在MBD 2-NuRD复合物之外起作用。此外，MBD 2在？还将在镰状细胞小鼠模型的背景下研究珠蛋白基因表达。通过将MBD 2-/-小鼠与镰状细胞小鼠杂交，我们将确定MBD 2的消融是否能够改善这种情况的影响。该项目对血红蛋白病患者（例如，镰状细胞性贫血和β地中海贫血），其中诱导？珠蛋白表达具有治疗效果。如果在体内模型中敲低MBD 2产生了？如先前在体外所显示的，珠蛋白，这使得这种蛋白质成为这些疾病中的良好靶标。此外，通过表征甲基胞嘧啶蛋白结合复合物的组分和相互作用，我们可以潜在地识别其他可能的靶点。这种有针对性的方法可能会产生一个更组织特异性的治疗条件，如地中海贫血，为临床医生提供更好的选择比目前的治疗。研究特定的蛋白质相互作用和基因表达机制导致了非常成功的靶向治疗的发展（特别是慢性粒细胞白血病的格列卫）。这是我研究的目标，以更好地了解将对未来治疗产生重大影响的过程。

DESCRIPTION (provided by applicant): MBD2 is thought to play a role in the silencing of certain genes by recruiting Mi2/NuRD repressor complex. To best study how the Mi2/NuRD complex plays a role in the silencing of ?-globin, we have set out to study this model in human hematopoietic progenitor cells. When cultured on a differentiation medium, these cells mimic the hemoglobin switch that occurs during development. Because knocking down Mi2 on mouse erythroid cells bearing the human ¿-locus had several fold greater effect than knocking down MBD2, Mi2 will be studied to determine if it acts outside of the MBD2-NuRD complex. Furthermore, the role of MBD2 in ?-globin gene expression will also be studied in the context of a sickle cell mouse model. By crossing MBD2-/- mice with sickle cell mice, we will determine whether ablation of MBD2 is able to ameliorate the effects of this condition. This project has clinical significance for patients with hemoglobinopathies (e.g., sickle cell anemia and beta thalassemia), where induction of ?-globin expression has a therapeutic effect. If knocking down MBD2 in an in vivo model produces a considerable change in the expression of ?-globin, as has been previously shown in vitro, this makes such protein a good target in these diseases. Moreover, by characterizing the components and interactions of the methylcytosine protein binding complex we could potentially identify other possible targets. This targeted approach may yield a more tissue-specific treatment to conditions such as ¿-thalasemia, providing clinicians with better options than current treatments. Studying specific protein interactions and mechanisms of gene expression has led to the development of highly successful targeted treatments (notably, Gleevec for Chronic Myelogenous Leukemia). This is the goal of my research, to build a better understanding of processes that will have a great impact on the future treatments.