Targeting the NuRD complex for fetal globin induction

摘要 血红蛋白病，如镰状细胞病（SCD）和地中海贫血，是最大的公共卫生 世界上的担忧。虽然新的治疗方式，如基因治疗，目前正在测试， 迫切需要治疗一般患者群体的药理学方法。我们的长期目标 开发一种化合物，其通过靶向转录因子来诱导胎儿型球蛋白（HbF）的产生， 复杂的调节珠蛋白转换。本申请的目的是确定分子机制 作为LRF-NuRD介导的γ-珠蛋白沉默的基础，并鉴定靶向它们的方法。我们的中央 假设是含LRF的NuRD复合物是HbF再激活疗法的潜在靶标。的 提出这项研究的理由是，了解LRF/NuRD介导的珠蛋白调节将 提供对调节γ-珠蛋白抑制的转录复合物的更好理解，并促进 HbF诱导治疗的新治疗策略的开发。根据初步数据，我们 我们希望通过以下三个具体目标来实现我们的目标：1）确定γ- 在LRF/NuRD不存在下的珠蛋白再激活; 2）鉴定γ-珠蛋白激活所必需的CHD 3/4的结构域。 3）确定LRF/CHD 3相互作用在控制γ-珠蛋白中的功能意义 沉默在Aim 1中，我们将采用ChIP-seq和ATAC-seq足迹法来确定NuRD- 相关途径沉默成人红系细胞中的γ-珠蛋白表达以及γ-珠蛋白是如何被诱导的 LRF耗尽。在Aim 2中，我们将鉴定负责γ-珠蛋白沉默的CHD 3/4的最小结构域。到 这样做，我们将使用CRISPR-Cas9基因诱变进行功能结构域定位。在AIM 3中，我们将 确定LRF/CHD 3相互作用在控制γ-珠蛋白沉默中的功能意义。我们的出版 工作和初步数据强烈表明，NuRD相关的途径，其中LRF和BCL 11 A 参与，代表了几乎全部的“球蛋白开关”。我们希望， 本文提出的将阐明LRF和NuRD复合物在γ-珠蛋白沉默中的作用，并促进 血红蛋白病的HbF再激活治疗的新策略的开发。

Abstract Hemoglobinopathies, such as sickle cell disease (SCD) and thalassemia, are among the greatest public health concerns in the world. Although new therapeutic modalities, such as gene therapy, are currently being tested, there is a pressing need for pharmacologic approaches to treat general patient populations. Our long-term goal is to develop a compound(s) that induces fetal-type globin (HbF) production by targeting the transcriptional complex regulating globin switching. The objective of this application is to determine molecular mechanisms underlying the LRF-NuRD-mediated γ-globin silencing and identify a mean(s) to target them. Our central hypothesis is that the LRF-containing NuRD complex is a potential target for HbF reactivation therapy. The rationale for the proposed research is that understanding the LRF/NuRD-mediated globin regulation will provide greater understanding of the transcriptional complex regulating γ-globin repression and facilitate development of novel therapeutic strategies for HbF induction therapy. Guided by strong preliminary data, we expect to achieve our objective by pursuing the three specific aims: 1) to determine the molecular basis for γ- globin reactivation in the absence of the LRF/NuRD; 2) to identify a domain(s) of CHD3/4 necessary for γ- globin silencing; and 3) to determine functional significance of LRF/CHD3 interaction in controlling γ-globin silencing. In Aim1, we will employ ChIP-seq and ATAC-seq foot-printing to determine how the NuRD- associated pathways silences γ-globin expression in adult erythroid cells and how γ-globin is induced upon LRF depletion. In Aim2, we will identify a minimal domain(s) of CHD3/4 responsible for γ-globin silencing. To do so, we will perform a functional domain mapping using CRISPR-Cas9 gene mutagenesis. In Aim3, we will determine functional significance of the LRF/CHD3 interaction in controlling γ-globin silencing. Our published work and preliminary data strongly suggest that the NuRD-associated pathways, in which LRF and BCL11A are involved, represent the near entirety of the “globin-switch”. We expect that the combined approaches proposed here will elucidate the role of LRF and the NuRD complex in γ-globin silencing and facilitate development of novel strategies for HbF reactivation therapy for hemoglobinopathies.