Epitranscriptomic control of erythropoiesis

红细胞生成的表观转录组控制

• 批准号: 10413027
• 负责人: Patrick Paddison
• 金额: $ 6.26万
• 依托单位: FRED HUTCHINSON CANCER CENTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-17 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10413027
• 关键词: Epitranscriptomic; control; erythropoiesis

PROJECT SUMMARY We recently found that N6-methyladenosine (m6A) mRNA regulation plays an essential role in human red blood cell development. We observed that genes coding for the m6A mRNA methyltransferase (MTase) complex, including, METTL14, METTL3, and WTAP, are required for promoting erythroid gene expression programs in human erythroid leukemia (HEL) cells and for the erythroid lineage specification in human primary, bipotent hematopoietic progenitor cells (HPCs). Critically, we find that m6A mRNA marks promote the translation of >200 genes, many of which play a role in erythroid lineage gene expression, and differentiation. Both Diamond- Blackfan anemia, and Myelodysplastic Syndromes are associated with mutations in these genes. The purpose of this grant is to elucidate how this novel form of gene regulation contributes to normal and abnormal erythropoiesis. To this end, in Aim 1, we test the hypothesis that m6A-mRNA marking promotes selective translation of genes required for human erythropoiesis. In Aim 2, we test the hypothesis that m6A marking of mRNAs coding for a network of SET domain histone/protein methyltransferase genes is critical for erythroid lineage specification. We will create a resource of all m6A mRNA marking events during human erythropoiesis, while examining the effect of m6A methylation on key erythroid transcriptional regulators (e.g., GATA1, IKZF1, KLF2, and ZFPM1) and whether specificity factors play roles in lineage-specific marking events. In Aim 3, we define the m6A-mRNA "methylome" for human adult erythropoiesis and hematopoiesis and ask whether m6A mRNA methylation is altered in myelodysplastic syndrome (MDS). Our interest in MDS stems from several observations. First, we found that m6A mRNA methylation occurs in 70 out of 104 genes associated with MDS, including 8 of the 10 most frequently mutated genes (e.g., TET2, SF3B1, ASXL1, RUNX1, DNMT3A, ZRSR2, and STAG2). Second, the blockage of erythroid lineage formation in human adult progenitors by inhibition of m6A MTase copies the phenotype of MDS-related anemias. Third, m6A-mRNA- sequencing pilot studies of multiple MDS patient samples provided evidence of significantly lower mRNA marking for networks of splicing genes and other key regulators of erythropoiesis (e.g., U2AF2 and KLF1). Approximately, one-third of patients with MDS progress to acute myeloid leukemia (AML), with poor outcomes. Although multiple somatic events have been implicated in MDS, including chromosomal abnormalities, mitochondrial (metabolic) dysfunction, abnormal expression of pro-inflammatory cytokines, and dysregulated erythropoiesis, none have been shown unequivocally to initiate or drive disease progression. The proposed studies will define the role that m6A-mRNA methylation plays in regulating normal erythropoiesis and determine whether altered m6A-mRNA contributes to the anemia of MDS.

项目概要 我们最近发现 N6-甲基腺苷 (m6A) mRNA 调节在人类红血中发挥着重要作用 细胞发育。我们观察到编码 m6A mRNA 甲基转移酶 (MTase) 复合物的基因， 包括 METTL14、METTL3 和 WTAP，是促进红系基因表达程序所必需的 人红细胞白血病 (HEL) 细胞以及人原代、双能细胞中的红细胞谱系规范 造血祖细胞（HPC）。重要的是，我们发现 m6A mRNA 标记促进 >200 基因，其中许多在红细胞谱系基因表达和分化中发挥作用。均为钻石- 黑扇贫血症和骨髓增生异常综合征与这些基因的突变有关。目的 这笔赠款的目的是阐明这种新型基因调控如何促进正常和异常 红细胞生成。为此，在目标 1 中，我们测试了 m6A-mRNA 标记促进选择性的假设 人类红细胞生成所需基因的翻译。在目标 2 中，我们检验了 m6A 标记的假设 编码 SET 结构域组蛋白/蛋白质甲基转移酶基因网络的 mRNA 对于红细胞至关重要 血统规范。我们将创建人类红细胞生成过程中所有 m6A mRNA 标记事件的资源， 同时检查 m6A 甲基化对关键红系转录调节因子（例如 GATA1、IKZF1、 KLF2 和 ZFPM1）以及特异性因子是否在谱系特异性标记事件中发挥作用。在目标 3 中，我们 定义成人红细胞生成和造血的 m6A-mRNA“甲基化组”，并询问 m6A 是否 骨髓增生异常综合征 (MDS) 中 mRNA 甲基化发生改变。 我们对 MDS 的兴趣源于一些观察结果。首先，我们发现 m6A mRNA 甲基化发生在 70 与 MDS 相关的 104 个基因中，包括 10 个最常见突变基因中的 8 个（例如 TET2、SF3B1、 ASXL1、RUNX1、DNMT3A、ZRSR2 和 STAG2）。二、人类红系谱系形成受阻 成年祖细胞通过抑制 m6A MTase 复制 MDS 相关贫血的表型。三、m6A-mRNA- 对多个 MDS 患者样本进行测序的初步研究提供了 mRNA 标记显着降低的证据 用于剪接基因网络和红细胞生成的其他关键调节因子（例如 U2AF2 和 KLF1）。大约， 三分之一的 MDS 患者进展为急性髓系白血病 (AML)，且预后不佳。虽然多 MDS 涉及体细胞事件，包括染色体异常、线粒体（代谢）异常 功能障碍、促炎细胞因子的异常表达和红细胞生成失调，但没有 已明确显示可引发或驱动疾病进展。 拟议的研究将确定 m6A-mRNA 甲基化在调节正常红细胞生成中的作用 并确定改变的 m6A-mRNA 是否会导致 MDS 贫血。