HEMATOPOIETIC RING FINGER 1 (HERF1) IN ERYTHROPOIESIS

红细胞生成中的造血环指 1 (HERF1)

• 批准号: 6650006
• 负责人: JAMES R DOWNING
• 金额: $ 12.63万
• 依托单位: ST. JUDE CHILDREN'S RESEARCH HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6650006
• 关键词: cell line; erythroid stem cell; erythropoiesis; gene expression; laboratory mouse; protein structure function; sickle cell anemia

This proposal focuses on defining at a mechanistic level, the role in erythropoiesis of a newly discovered gene, HERF1, that we cloned as a downstream target of the AML1/CBFbeta transcription factor complex. The HERF1 protein contains an N-terminal RING-finger domain followed by a single B-box motif, a leucine coiled-coil domain, and a C-terminal rfp homologous region. Expression of HERF1 during embryogenesis coincides with the appearance of definitive erythropoiesis and, in adult mice, is restricted to the erythroid lineage, increasing over 40-fold during terminal differentiation. Importantly, we have demonstrated that inhibition of HERF1 expression blocks terminal erythroid differentiation, whereas over-expression of HERF1 in erythroid cells induces beta-major globin expression and erythroid differentiation. Taken together, these results suggest that HERFF1 plays an essential role in the development of mature erythroid cells. The studies in this project seek to elucidate, at a mechanistic level, the role of HERF1 in the linage commitment and maturation of erythroid progenitors. Our working hypothesis is that HERF1 functions as a part of a multiprotein complex to regulate cellular pathways required for the development and terminal differentiation of erythroid cells. Experiments are proposed in specific aim 1 to examine the biologic role of HERF1 in erythroid development through generation of both HERF1-deficient ES cells and mice, as well as murine systems with enforced HERF1 expression. In experiments outlined in specific aim 2, we will investigate the biochemical mechanism of action of HERF1 to gain insight into its mechanistic role in erythroid cell development. Together, these studies should provide important information on critical regulatory pathways required for the normal development of cells of the erythroid lineage. This fundamental knowledge is likely to expand our abilities to rationally manipulate erythroid lineage functions, potentially for therapeutic purposes in sickle cell anemia

这项建议的重点是在机制水平上定义一个新发现的基因HERF1在红细胞生成中的作用，该基因是我们克隆的AML1/CBFβ转录因子复合体的下游靶标。HERF1蛋白含有一个N-末端的环指结构域、一个B-box基序、一个亮氨酸卷曲结构域和一个C-末端的RFP同源区。HERF1在胚胎发育期间的表达与明确的红细胞生成相一致，在成年小鼠中，仅限于红系，在终末分化过程中增加40倍以上。重要的是，我们已经证明，抑制HERF1的表达阻止了红系的终末分化，而HERF1在红系细胞中的过度表达诱导了β-主要珠蛋白的表达和红系的分化。综上所述，这些结果表明HERFF1在成熟红系细胞的发育过程中起着重要的作用。本项目的研究试图在机制水平上阐明HERF1在红系祖细胞系承诺和成熟中的作用。我们的工作假设是，HERF1作为多蛋白复合体的一部分，调节红系细胞发育和终末分化所需的细胞通路。为了研究HERF1在红系发育中的生物学作用，通过产生HERF1缺陷的ES细胞和小鼠，以及增强表达HERF1的小鼠系统，提出了特定目标1的实验。在特定目标2中概述的实验中，我们将研究HERF1的生化作用机制，以深入了解其在红细胞发育中的机制作用。总之，这些研究应该提供有关红系细胞正常发育所需的关键调控途径的重要信息。这一基础知识可能会扩大我们合理操作红系血统功能的能力，可能用于治疗镰状细胞性贫血。