Probing the coordination of cell cycle progression and differentiation in hematopoietic stem cells

探讨造血干细胞细胞周期进程和分化的协调

基本信息

批准号：
10687421
负责人：
Gregory David
金额：
$ 53.86万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-07 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10687421
关键词：
ATAC-seq Adult Biological Assay Blood Blood Cells Bone Marrow Bone marrow failure Cell Cycle Cell Cycle Progression Cell Cycle Regulation Cell Cycle Stage Cells ChIP-seq Chromatin Chromatin Remodeling Factor Computer Analysis Data Embryo Environment Generations Genetic Genetic Transcription Goals Hematological Disease Hematopoiesis Hematopoietic Hematopoietic System Hematopoietic stem cells Histones Homeostasis Impairment In Vitro Individual Interferons Label Link Location Maintenance Molecular Neoplasms Pathologic Pathway interactions Phase Phenotype Positioning Attribute Process Production Property Reagent Recording of previous events Reporter Reporting Repression Research Scaffolding Protein Signal Pathway Signal Transduction Stimulus Stress Testing Therapeutic Time Transcriptional Activation Work adult stem cell base bone marrow failure syndrome cdc Genes clinically relevant experimental study genome-wide hematopoietic differentiation hematopoietic stem cell differentiation hematopoietic stem cell expansion hematopoietic stem cell self-renewal in vivo mutant novel marker novel therapeutics programs residence response self-renewal single cell analysis stem stem cell function tool transcription factor transcriptomics

项目摘要

ABSTRACT Hematopoietic stem cells (HSCs) generate all mature blood cells in adults. They remain quiescent at homeostasis but when needed, can reenter the cell cycle to either self-renew or differentiate and replenish the hematopoietic system. While the pathways governing HSC self-renewal are just being uncovered, what dictates HSC differentiation remains largely elusive. Recent studies indicate that residence in discrete phases of the cell cycle potentiates differentiation in embryonic and adult stem cells of different origins. However, the impact of cell cycle residence on HSC differentiation has not been directly explored. Here, we report the hematopoietic phenotypes elicited upon genetic inactivation of the chromatin modifier Sin3B. Sin3B serves as a scaffold protein that tethers repressive activities to discrete loci by interacting with sequence-specific transcription factors and histone modifiers. Through its ability to modulate transcription of cell cycle genes Sin3B restricts progression through the early phases of the cell cycle. Sin3B-deleted HSCs retain their self- renewal capacities, but they are unable to properly differentiate. The appropriate expression of lineage specification transcription factors suggests that alterations of the chromatin landscape likely dictate the defective differentiation in Sin3B-/- HSCs. Thus, Sin3B inactivation provides a unique opportunity to study the processes linking cell cycle progression with the generation of a transcriptional environment permissive for HSC differentiation. Our central hypothesis is that the ability of HSCs to differentiate is restricted to a discrete window within the early phase of the cell cycle. We will test the possibility that loss of Sin3B induces spurious progression through early stages of the cell cycle, which is incompatible with proper HSC differentiation, due to alterations in the chromatin landscape. We propose here to: Establish whether Sin3B-dependent restriction of cell cycle progression enables HSC differentiation (aim 1). Using cell cycle reporters, lineage tracing tools and single cell transcriptomic analyses, we will leverage the phenotypes elicited upon Sin3B inactivation to determine the functional relationship between cell cycle progression and differentiation in HSCs; and Determine the molecular bases for Sin3B-dependent differentiation in HSCs (aim 2).Through chromatin accessibility assays and genome-wide mapping of histone marks, we will determine the chromatin features that enable HSCs to respond to pro-differentiation stimuli during cell cycle progression. Based on our preliminary data, we will test the hypothesis that specific signaling pathways we found altered in Sin3B-/- HSCs, including the tonic interferon response, modulate the ability of HSCs to differentiate. Our proposed work will define an understudied molecular link between cell cycle progression and hematopoietic differentiation, pointing to potential approaches to modulate HSC expansion and differentiation for therapeutic purposes.

抽象的造血干细胞（HSC）产生成人所有成熟的血细胞。他们保持静止状态体内平衡，但在需要时，可以重新进入细胞周期以自我更新或分化和补充造血系统。虽然控制 HSC 自我更新的途径刚刚被发现，但什么是表明 HSC 的分化在很大程度上仍然难以捉摸。最近的研究表明，离散阶段的居住细胞周期的改变增强了不同来源的胚胎干细胞和成体干细胞的分化。然而，细胞周期停留对 HSC 分化的影响尚未被直接探索。在此，我们报道染色质修饰剂 Sin3B 基因失活后引发造血表型。 Sin3B 充当一种支架蛋白，通过与序列特异性相互作用将抑制活性束缚于离散基因座转录因子和组蛋白修饰剂。通过其调节细胞周期基因转录的能力 Sin3B 限制细胞周期早期阶段的进展。 Sin3B 删除的 HSC 保留其自身更新能力，但他们无法正确区分。血统的恰当表达规范转录因子表明染色质景观的改变可能决定 Sin3B-/- HSC 的分化缺陷。因此，Sin3B 失活提供了一个独特的机会来研究将细胞周期进程与允许转录的环境的产生联系起来的过程 HSC分化。我们的中心假设是 HSC 的分化能力仅限于离散的细胞周期早期阶段的窗口。我们将测试 Sin3B 丢失导致杂散的可能性细胞周期早期阶段的进展，这与适当的 HSC 分化不相容，因为染色质景观的改变。我们在此建议：确定是否依赖于 Sin3B 的限制细胞周期进程促进 HSC 分化（目标 1）。使用细胞周期记者、谱系追踪工具和单细胞转录组分析，我们将利用 Sin3B 失活引起的表型来确定 HSC 细胞周期进程和分化之间的功能关系；和确定 HSC 中 Sin3B 依赖性分化的分子基础（目标 2）。通过染色质通过可及性测定和组蛋白标记的全基因组图谱，我们将确定染色质特征使 HSC 在细胞周期进程中能够对促分化刺激做出反应。根据我们的初步数据，我们将测试我们发现 Sin3B-/- HSC 中特定信号通路发生改变的假设，包括强直性干扰素反应，调节 HSC 的分化能力。我们提出的工作将定义一个细胞周期进程和造血分化之间的分子联系尚未得到充分研究，指出调节 HSC 扩增和分化以达到治疗目的的潜在方法。