Mechanisms of epiblast and primitive endoderm segregation

外胚层和原始内胚层分离的机制

基本信息

批准号：
10566100
负责人：
Eszter Posfai
金额：
$ 44.46万
依托单位：
PRINCETON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-02-07 至 2028-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10566100
关键词：
3-Dimensional ATAC-seq Address Automobile Driving Binding Biological Models Biosensor Caenorhabditis elegans Capsicum Cell Communication Cell Cycle Progression Cell Differentiation process Cells Characteristics Chromatin Color Complex Cues Data Data Set Development Developmental Process Drosophila genus Educational process of instructing Embryo Embryonic Development Endoderm Endoderm Cell Ensure Environment Epiblast Fetus Fibroblast Growth Factor Gene Expression Gene Expression Profile Genetic Genetic Transcription Genetic study Genome engineering Genomic approach Genomics Heterogeneity Human Image Image Analysis Implant Individual Inherited Inner Cell Mass Lead Mammals Modeling Molecular Morphology Mothers Mus Nature Neighborhoods Nucleic Acid Regulatory Sequences Organism Outcome Pattern Population Positioning Attribute Pregnancy loss Process Recording of previous events Reporter Reproducibility Resolution Shapes Signal Transduction Sodium Chloride Sorting Source Specific qualifier value Statistical Data Interpretation Stereotyping Structure Techniques Technology Testing Time Uterus Variant Visualization Work analysis pipeline blastocyst cell fate specification cell type developmental disease embryo cell fascinate flexibility genome-wide image processing imaging approach insight intercellular communication mathematical model model organism novel pharmacologic preimplantation programs segregation temporal measurement tool transcription factor

3-Dimensional ATAC-seq Address Automobile Driving Binding Biological Models Biosensor Caenorhabditis elegans Capsicum Cell Communication Cell Cycle Progression Cell Differentiation process Cells Characteristics Chromatin Color Complex Cues Data Data Set Development Developmental Process Drosophila genus Educational process of instructing Embryo Embryonic Development Endoderm Endoderm Cell Ensure Environment Epiblast Fetus Fibroblast Growth Factor Gene Expression Gene Expression Profile Genetic Genetic Transcription Genetic study Genome engineering Genomic approach Genomics Heterogeneity Human Image Image Analysis Implant Individual Inherited Inner Cell Mass Lead Mammals Modeling Molecular Morphology Mothers Mus Nature Neighborhoods Nucleic Acid Regulatory Sequences Organism Outcome Pattern Population Positioning Attribute Pregnancy loss Process Recording of previous events Reporter Reproducibility Resolution Shapes Signal Transduction Sodium Chloride Sorting Source Specific qualifier value Statistical Data Interpretation Stereotyping Structure Techniques Technology Testing Time Uterus Variant Visualization Work analysis pipeline blastocyst cell fate specification cell type developmental disease embryo cell fascinate flexibility genome-wide image processing imaging approach insight intercellular communication mathematical model model organism novel pharmacologic preimplantation programs segregation temporal measurement tool transcription factor

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项目摘要

Abstract Embryonic development is a fascinating process during which different cells types are made and organized into complex and functional structures, ultimately building an entire organism. If we watch embryos develop, patterns emerge with remarkable reproducibility. However, if we zoom in to the level of individual cells, the scene, especially during mammalian development, often seems chaotic. Cells move around, change shape, contact different neighbors and show fluctuations in their gene expression patterns. Yet from this apparent chaos, robust and reproducible patterns emerge. How are the right cell types made at the right time and place in correct proportions? In this proposal we will use a crucial cell fate decision in the preimplantation mouse embryo, when the inner cell mass (ICM) lineage segregates into the epiblast (EPI) and the primitive endoderm (PE) lineages, the cell types that will give rise to most of the fetus and extraembryonic cell types, respectively, as a model system to reveal fundamental insights into the molecular and cellular mechanisms that ensure robust and reproducible lineage formation. While studies employing genetic and pharmacological approaches have established the necessary molecular players involved in EPI and PE cell fates, these are limited in providing temporal information on an inherently dynamic process. Additionally, ICM cells differentiate into EPI and PE cell types in a seemingly random pattern, which varies from one embryo to the next, complicating the interpretation of analysis performed only at fixed time points. Here we develop novel genetically encoded fluorescent reporter mouse lines for key factors involved in EPI and PE cell fates, which allow us to visualize and probe the mechanisms of cell fate acquisition with unprecedented spatial and temporal resolution, using a combination of cutting-edge live imaging, computational image processing, and genomics approaches. Using these powerful tools, we will investigate the mechanism driving initial symmetry-breaking in the ICM to initiate EPI/PE lineage differentiation and determine whether purely stochastic fluctuations or more predictable systematic variations present in the embryo are responsible for initiating this fate decision. Next, we will determine how cell fates are propagated over space and time to achieve reproducible cell-type proportions, by uniquely visualizing multiple nodes in cell-cell communication signaling. Finally, we will use recently developed genomics techniques to probe transcription factor occupancy and chromatin accessibility to observe how cell type-specific transcriptional programs are set up by key factors during EPI/PE lineage segregation. This work will uncover fundamental mechanisms by which variable developmental process can lead to robust and reproducible developmental patterning in the early mammalian embryo.

抽象的胚胎发育是一个引人入胜的过程，在此过程中，将不同的细胞类型制成并组织到复杂而功能的结构，最终建立整个生物体。如果我们观看胚胎的发展，图案具有显着的可重复性。但是，如果我们放大单个单元格的水平，场景，尤其是在哺乳动物发育期间，通常看起来很混乱。细胞四处移动，改变形状，接触不同的邻居并在其基因表达模式中显示出波动。然而，由于这种明显的混乱，并出现可再现图案。正确的单元类型在正确的时间和位置如何正确比例？在此提案中，我们将在植入前小鼠胚胎中使用关键的细胞命运决定，内部细胞质量（ICM）谱系将分离为层状（EPI）和原始内胚层（PE）谱系，将产生大多数胎儿和胚外细胞类型的细胞类型作为模型揭示对分子和细胞机制的基本见解的系统，以确保可靠和可再现的谱系形成。而采用遗传和药理方法的研究具有建立了参与EPI和PE细胞命运的必要分子参与者，这些分子在提供时受到限制有关固有动态过程的时间信息。另外，ICM细胞分化为EPI和PE细胞看似随机的模式的类型，从一个胚胎到下一个胚胎，使解释变得复杂分析仅在固定时间点执行。在这里，我们开发了新型遗传编码的荧光报告基因 EPI和PE细胞命运涉及的关键因素的小鼠线，这使我们能够可视化和探测使用前所未有的空间和时间分辨率的细胞命运获取机制，结合尖端的实时成像，计算图像处理和基因组学方法。使用这些功能强大工具，我们将调查在ICM中驱动初始对称性的机制以启动Epi/PE谱系分化并确定纯粹随机波动或更可预测的系统变化胚胎中的存在负责发起这一命运决定。接下来，我们将确定细胞命运是如何的通过唯一可视化多个，在空间和时间上传播以实现可重复的细胞型比例细胞电池通信信号传导中的节点。最后，我们将使用最近开发的基因组技术来探测转录因子占用率和染色质的可及性，以观察细胞类型特异性转录程序由EPI/PE谱系隔离期间的关键因素设置。这项工作将揭示基本可变发展过程可以导致鲁棒和可重复发展的机制在早期的哺乳动物胚胎中图案。