Molecular and Architectural Mechanisms of Reprogramming to Pluripotency

重编程为多能性的分子和结构机制

• 批准号: 8710262
• 负责人: Kathrin Plath
• 金额: $ 222.17万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8710262
• 关键词: Address; Area; Autologous; Bioinformatics; Biopsy Specimen; Cell Nucleus; Cell Transplantation; Cells; Chromatin; Collaborations; Competence; Disease model; Effectiveness; Epigenetic Process; Funding; Genetic Transcription; Genome; Genomics; Goals; High-Throughput Nucleotide Sequencing; Higher Order Chromatin Structure; Human; In Vitro; Institution; Knowledge; Maintenance; MicroRNAs; Molecular; Nuclear; Pluripotent Stem Cells; Process; Publications; Reagent; Research Personnel; Resource Sharing; Services; Site; Stem cells; Techniques; Time; data sharing; in vivo; insight; interest; pluripotency; programs; self-renewal; stem cell biology; stem cell differentiation; transcription factor; web site

DESCRIPTION (provided by applicant): The long-term objective of this Program is to determine the fundamental mechanisms underlying the interplay between transcription factors, chromatin structure, and higher-order genomic organization during the cellular conversion to and maintenance of pluripotency. Despite the remarkable ability of transcription factors and miRNAs to convert cells to pluripotency, undefined stochastic parameters presently limit the efficiency of the process. In addition, different pluripotent lines have different capacities for terminal differentiation and we poorly understand parameters that determine how well in vitro differentiation compares to in vivo differentiation. Understanding the molecular mechanisms in pluripotency induction and maintenance as well as those limiting differentiation will allow enhancements of the process that, in turn, will facilitate the use of small human biopsy samples much more efficiently than present techniques allow. To this end, the four projects of the Program ask: 1) How is the differentiated cell genome reorganized within the nucleus, during reprogramming to pluripotency, what aspects of reorganization are important, and what controls genome organization in pluripotent cells? 2) How do ectopic pluripotency transcription factors gain access to silent, chromatinized target sites to activate the endogenous pluripotency network, and how can the process be enhanced? 3) What regulatory circuits need to be properly established within pluripotent cells to allow their subsequent differentiation to fully mature progeny? 4) What marks of the competence to differentiate exist in pluripotent cells and how do they get established? By seeking answers to these questions in a single Program, we can obtain a time-resolved, integrated view of the mechanisms by which different aspects of the nuclear genome change coordinately to properly convert a cell to pluripotency and the process by which cells return to the somatic state. We also anticipate that the coordinate mechanisms unveiled by our studies will provide insights into direct cell reprogramming, independent of pluripotency. Administrative and Bioinformatics Cores and a shared Web site will support the projects with integrated services for optimal quality, efficiency, and data-sharing. The Administrative Core leverages existing high throughput sequencing, microarray, and stem cell cores at the respective institutions. The Project and Core leaders have complementary expertise in the relevant areas of stem cell biology, differentiation, transcription and chromatin/ epigenetics and have a long-standing record of interactive collaborations and publications. The plan provides unique experimental synergies that address the objectives of the funding announcement.

描述（由申请人提供）：该程序的长期目标是确定在细胞转换到多能性的细胞转换和维持过程中转录因子，染色质结构和高阶基因组组织之间相互作用的基本机制。尽管转录因子和miRNA具有明显的能力，可以将细胞转换为多能性，但目前未定义的随机参数仍限制了该过程的效率。另外，不同的多能线具有不同的终端分化能力，我们不了解参数，这些参数决定了体外分化与体内分化的比较。了解多能诱导和维持中的分子机制以及限制分化的分子机制将使过程增强，而过程又将促进与当前技术相比，促进小型人类活检样品的使用效率更高。为此，该程序的四个项目提出：1）分化细胞基因组如何在细胞核内重组，重新编程到多能性，重组的哪些方面很重要，什么控制多能细胞中的基因组组织？ 2）异位多能转录因子如何进入静音，染色体化的目标位点以激活内源性多能网络，以及如何增强该过程？ 3）需要在多能细胞中正确确定哪些调节回路以使其随后的分化以完全成熟的后代？ 4）多能细胞中存在哪些差异能力的标记？如何建立它们？通过在单个程序中寻求对这些问题的答案，我们可以获得时间分辨的，综合的视图，核基因组的不同方面会协同变化以正确地将细胞转换为多能性和细胞返回躯体状态的过程。我们还预计，我们的研究揭示的坐标机制将为直接细胞重编程提供见解，而与多能性无关。行政和生物信息学核心以及共享网站将通过集成服务为项目提供最佳的质量，效率和数据共享。管理核心利用各自机构的现有高通量测序，微阵列和干细胞内核。该项目和核心领导者在干细胞生物学，分化，转录和染色质/表观遗传学的相关领域具有互补的专业知识，并具有互动合作和出版物的长期记录。该计划提供了独特的实验协同作用，可以解决资金公告的目标。