Studying epigenetic dysregulation in Down Syndrome using fluorescent reporter cell lines

使用荧光报告细胞系研究唐氏综合症的表观遗传失调

• 批准号: 10432293
• 负责人: ELLA ZELDICH
• 金额: $ 8.25万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-01 至 2024-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10432293
• 关键词: Affect; Antibiotics; Antibodies; Architecture; Astrocytes; Automobile Driving; Binding; Brain; CRISPR/Cas technology; Cell Line; Cell Lineage; Cell Separation; Cell Surface Proteins; Cells; Cellular Assay; Chromatin; Chromatin Structure; Chromium; Chromosome 21; Clustered Regularly Interspaced Short Palindromic Repeats; DNA; Deacetylation; Development; Down Syndrome; Down-Regulation; Engineering; Epigenetic Process; Etiology; Fiber; Fluorescence-Activated Cell Sorting; Genes; Genetic; Genetic Transcription; Genome Stability; Goals; Hand; Histones; Human; Human Chromosomes; Human Engineering; Intellectual functioning disability; Laboratories; Link; Magnetism; Maintenance; Masks; Measures; Methylation; Molecular; Monitor; Mus; Myelin; Nature; Neurons; Oligodendroglia; Pathway Analysis; Patients; Pattern; Peptides; Persons; Platelet-Derived Growth Factor alpha Receptor; Population; Prevalence; Production; Proliferating; Proteins; Protocols documentation; Publishing; Quality of life; Reporter; Reporting; Reproducibility; Resolution; Sampling; Structure; System; Tissue Sample; Transposase; Trisomy; Universities; Visualization; antibody detection; astrocyte progenitor; base; brain tissue; cell type; density; epigenome; gene network; gliogenesis; human RNA sequencing; human embryonic stem cell; improved; induced pluripotent stem cell; motor disorder; myelination; oligodendrocyte lineage; oligodendrocyte progenitor; progenitor; sequencing platform; stem cells; transcriptome; transcriptomics; white matter

Abstract: The exact etiology of the intellectual disability in Down syndrome (DS) is unknown. Triplication of human chromosome 21 (HSA21) results in widespread changes across the entire epigenome and transcriptome. Recent studies have identified dysregulated gene networks related to oligodendrocyte (OL) development, differentiation, and myelin maintenance in human and mouse DS brains. These transcriptional changes manifest in the delayed onset of myelination, reduced density of myelinated fibers, disruption in their lattice-like organization, and decreased conduction velocity across myelinated fibers, implying that aberrant gliogenesis and white matter alterations in trisomic brains contribute to intellectual deficits in DS. Furthermore, in contrast to the reduction of OLs, an expanded population of astrocytes has been reported in DS. OL cell specification and differentiation is tightly controlled through stage-specific acquisition of defined chromatin marks. Distinct epigenetic signatures, including differing patterns of DNA deacetylation and methylation, and altered histone marks have been observed in DS. Thus, the dysregulation of the genes driving OL development and maturation may be a consequence of aberrant DS-related epigenetic architecture resulting in perturbed OL production and the white matter deficit observed in DS. In our preliminary studies, we differentiated OLs from isogenic trisomic and euploid control induced pluripotent stem cells (iPSCs) derived from people with DS and identified trisomy-related dysregulation of OL commitment, development, and maturation. However, the heterogeneous culture inherent to the published protocol limits downstream analysis and identification of functionally and transcriptionally distinct OL subtypes as well as examination of their developmental trajectories in DS. Thus, our goal is to engineer two isogenic DS-derived iPSC lines to express tdTomato under the control of the endogenous platelet-derived growth factor receptor α (PDGFRα) locus to facilitate the study of the molecular etiology of the white matter deficit in DS. PDGFRα is primarily expressed in proliferating OPCs and PDGFRα+ progenitors, giving rise to mature OLs as well as astrocytes. Thus, DS-derived PDGFRα reporter lines will allow to examine changes in gliogenesis, the imbalance in OL and astrocyte production, and monitor OL development and maturation. Using these lines, we will perform single cell assay for transposase-accessible chromatin (ATAC)-seq to examine how changes in chromatin accessibility affect OL lineage developmental trajectory in DS patient-derived cells. Our studies will conceptually link DS-associated alterations in OL differentiation to the epigenetic architecture as the underlying cause for abnormal OL development leading to the intellectual deficits in DS.

抽象的： 唐氏综合症（DS）中智力残疾的确切病因尚不清楚。人类的三分之一 染色体21（HSA21）导致整个表观基因组和转录组的宽度变化。最近的 研究已经确定了与少突胶质细胞（OL）发育，分化， 以及人和老鼠DS大脑中的髓磷脂维护。这些转录变化在延迟 髓鞘形成的发作，髓鞘纤维的密度降低，类似晶格的组织中断，以及 骨髓纤维的传导速度降低，这意味着异常的神经胶质和白质 三化大脑的改变会导致DS中的智力缺陷。此外，与减少相反 OLS在DS中据报道，已扩大的星形胶质细胞数量扩大。 OL细胞规范和分化通过定义的特定阶段的习得严格控制 染色质标记。独特的表观遗传特征，包括不同的DNA脱乙酰化模式和 在DS中观察到甲基化和组蛋白标记的改变。那，驱动基因的失调 OL开发和成熟可能是导致异常DS相关表观遗传结构的结果 在ds中观察到的扰动OL产生和白质缺陷中。在我们的初步研究中，我们 从等源性三体和多倍体控制的分化OLS诱导的多能干细胞（IPSC）衍生自 患有DS并确定了与OL承诺，发展和成熟的失调失调。 但是，异质文化继承了已发表的协议限制下游分析和 识别功能和转录不同的OL亚型以及检查其 DS中的发展轨迹。这是我们的目标是设计两个等源性DS衍生的IPSC线以表达 TDTOMATO在内源性血小板衍生的生长因子受体α（PDGFRα）基因座的控制下 促进DS中白质不足的分子病因研究。 PDGFRα主要在 增殖的OPC和PDGFRα+祖细胞，导致成熟的OL和星形胶质细胞。那是DS的衍生 PDGFRα报告基线将允许检查神经胶质发生的变化，OL和星形胶质细胞的不平衡 生产并监测OL的开发和成熟。使用这些行，我们将对 转座酶可访问的染色质（ATAC）-Seq，以检查染色质可及性的变化如何影响OL DS患者衍生细胞中的谱系发育轨迹。我们的研究将在概念上将与DS相关的 OL与表观遗传结构的差异变化是异常的根本原因 发展导致DS的智力缺陷。