Targeting ZNF410 for HbF reactivation

摘要 血红蛋白疾病，如镰状细胞病和β-地中海贫血，是最常见的单基因 然而，目前的治疗在很大程度上仍然是支持性的和不充分的。引产胎儿 血红蛋白(HBF)可以绕过导致这些疾病的成人血红蛋白的基本遗传缺陷。 疾病。最近的基因治疗的成功提供了概念的证明，理解分子控制 成人期的HBF沉默可以确定合理的治疗靶点。然而，基因治疗不能扩大规模。 在全球范围内与可预见的未来的临床问题的范围相匹配。因此，小说 需要药物治疗才能诱发HBF。HBF的主要调节器BCL11A、ZBTB7A和NuRD分别 具有靶向责任，这可能使治疗靶向具有挑战性。最近发现了ZNF410 成为成人期红细胞生成过程中HBF水平的新型转录抑制因子。ZNF410有一个狭窄的 生物学作用，即增强CHD4的表达。CHD4拥有27个唯一的数组 重复了ZNF410启动子和上游增强子的结合基序，这是一个没有可比性的组合 在基因组的其余部分。本研究旨在探讨ZNF410控制的机制。 CHD4通过同型基序簇的表达；对ZNF410及其同源基因贯穿始终的要求 ZNF410的发育、动态平衡和造血；以及通过 IMiD同系物作为一种治疗方法。近期目标是确定蛋白质水平的协同性的作用 ZNF410与CHD4结合中的染色质可及性及其相互关系 事件和CHD4的表达。这些机械性研究将有助于识别这一监管轴心中的脆弱性 这可能是治疗上的目标。此外，ZNF410在小鼠发育和发育过程中的作用 成年期以及人类造血能力都将被研究。的结构性和条件性等位基因 Zfp410及其在CHD4小鼠体内的同源调控元件将被产生并鉴定。 ZNF410在整个人类红细胞生成和造血过程中的需求将通过批量和 体外和体内单细胞基因表达和染色质图谱。最后，工具化合物将是 用于验证小分子对ZNF410的靶向蛋白质降解作为一种有前景的治疗方法 接近。将利用结构评估和对结构-活动关系的系统探索 在ZNF410/Zfp410中获得有指导意义的化合物以评价细胞和动物的充足和不足 模拟治疗前提，即ZNF410是诱导β-HbF的有利治疗靶点。 血红蛋白病。长期目标是促进类药物小分子的发展， 最终可以用于临床试验。

ABSTRACT Hemoglobin disorders, such as sickle cell disease and β-thalassemia, comprise the most common monogenic diseases of the world and yet, current treatments remain largely supportive and inadequate. Induction of fetal hemoglobin (HbF) could bypass the fundamental genetic defects of adult hemoglobin that cause these diseases. Recent gene therapy successes provide proof-of-concept that understanding the molecular control of adult-stage HbF silencing can identify rational therapeutic targets. However, gene therapy cannot be scaled up globally to match the scope of the clinical problem for the foreseeable future. Therefore, novel pharmacotherapies are needed to induce HbF. The major HbF regulators BCL11A, ZBTB7A, and NuRD each have on-target liabilities that could make therapeutic targeting challenging. Recently ZNF410 was discovered to be a novel transcriptional repressor of HbF level during adult-stage erythropoiesis. ZNF410 has a narrow biological action, which is to enhance the expression of CHD4. CHD4 possesses a unique array of 27 reiterated ZNF410 binding motifs at its promoter and upstream enhancer, an assemblage without comparison in the rest of the genome. This study aims to investigate the: mechanisms whereby ZNF410 controls the expression of CHD4 through homotypic motif clusters; requirements for ZNF410 and its orthologs throughout development, homeostasis and hematopoiesis; and potential of targeted protein degradation of ZNF410 by IMiD congeners as a therapeutic approach. Near-term goals are to define the role of protein-level cooperativity and chromatin accessibility in binding to CHD4 by ZNF410 and the relationship between ZNF410 binding events and CHD4 expression. These mechanistic studies will help identify vulnerabilities in this regulatory axis that might be targeted therapeutically. Furthermore, the roles of ZNF410 throughout mouse development and adulthood as well as in human hematopoiesis will be investigated. Constitutive and conditional alleles of Zfp410 and its cognate regulatory elements at Chd4 in mice will be generated and characterized. Requirements for ZNF410 throughout human erythropoiesis and hematopoiesis will be identified by bulk and single cell gene expression and chromatin profiling in vitro and in vivo. Finally, tool compounds will be generated to validate targeted protein degradation of ZNF410 by small molecules as a promising therapeutic approach. Structural evaluation and systematic exploration of structure-activity relationships will be leveraged to obtain instructive compounds to evaluate in ZNF410/Zfp410 sufficient and deficient cellular and animal models the therapeutic premise that ZNF410 is a favorable therapeutic target for HbF induction in the β- hemoglobinopathies. The long-term goal is to promote the development of drug-like small molecules that ultimately could be used in clinical trials.