Deciphering and overcoming epigenetic erosion at imprinted loci in mouse and human naive pluripotent stem cells

破译并克服小鼠和人类幼稚多能干细胞印记位点的表观遗传侵蚀

• 批准号: BB/R018588/1
• 负责人: Kevin Chalut
• 金额: $ 53.23万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FR018588%2F1
• 关键词: Deciphering; overcoming; epigenetic; erosion; imprinted

During the routine petri dish culture of naïve pluripotent stem cells it was found that these acquire errors in a group of genes named imprinted. Naïve pluripotent stem cells are cells that represent the very earliest stage of embryonic development, and have the ability to self-replicate exactly or to change into any cell type in the body. Imprinting is a phenomenon that leads to genes being expressed in a parent of origin specific manner. This process involves modifications, DNA methylation and histone methylation, at regulatory regions of imprinted genes that affects their expression. These imprint marks are naturally erased and established in the germline of the parents and are subsequently maintained in all the other cells (soma) from the fertilized egg till adulthood. Abnormally, these imprints are erased in the routine petri dish culture of naïve pluripotent stem cells hindering the potential of these cells. My group has recently discovered a gene, Impera, that potentially directs the observed removal of imprints at imprinted genes. Now we want to define mechanistically how Impera works and to define strategies that prevent Impera from inducing imprint erasure. Achieving these goals will lead to a fundamental discovery in developmental biology, the first identified gene capable of mediating imprint erasure, and to the prevention of imprint erasure in the cultures of both mouse and human naïve pluripotent stem cells. In the medical context, appropriate imprinting is important for normal development. Human diseases involving inappropriate/lack of imprinting include Angelman syndrome and Prader-Willi syndrome. Thus, understanding mechanistic how imprint erasure occurs may uncover pathways and processes that will enhance our understanding of pathological processes. Naïve pluripotent stem cells are also widely used as a platform for early developmental research, with much investment being focussed on both understanding how cells maintain their naïve state and how they commit to becoming specific cell types. The proposed research will provide insights into how we might be able to stabilise stem cells in this naïve state, providing more stable stem cell platforms for use as a research tool, in drug discovery programmes and in regenerative medicine applications. Our research group has a strong track record in stem cell biology and has the necessary expertise to successfully complete this important project. Further, working within the Cambridge Stem Cell Institute puts us in a strategically strong position, with close collaborators including Dr Kevin Chalut. An expert in the physical biology of pluripotency and differentiation which together with my lab developed a novel hydrogel protocol (manuscript in preparation) which supports naïve pluripotent stem cell self-replication. This may prove a very useful tool in our aim to generate naïve pluripotent stem cells free of imprint errors

在对幼稚多能干细胞进行常规培养的过程中，发现这些细胞在一组名为印记的基因中获得错误。幼稚多能干细胞是代表胚胎发育最早阶段的细胞，具有精确自我复制或转变为体内任何细胞类型的能力。印迹是一种导致基因以亲本来源特异性方式表达的现象。这一过程涉及影响印迹基因表达的调控区域的修饰，即DNA甲基化和组蛋白甲基化。这些印记标记被自然地擦除并在父母的生殖系中建立，并且随后从受精卵直到成年保持在所有其他细胞（索马）中。不正常的是，这些印记在幼稚多能干细胞的常规培养皿中被抹去，阻碍了这些细胞的潜力。我的团队最近发现了一种基因，Impera，它可能指导观察到的印记基因的印记去除。现在，我们想从机械上定义Impera是如何工作的，并定义防止Impera引起印记擦除的策略。实现这些目标将导致发育生物学的根本性发现，即第一个识别出的能够介导印记擦除的基因，并防止小鼠和人类幼稚多能干细胞培养物中的印记擦除。在医学方面，适当的印记对正常发育很重要。涉及印记不适当/缺乏的人类疾病包括Angelman综合征和Prader-Willi综合征。因此，理解印记擦除发生的机制可能会揭示将增强我们对病理过程的理解的途径和过程。幼稚多能干细胞也被广泛用作早期发育研究的平台，大量投资集中在了解细胞如何保持幼稚状态以及它们如何致力于成为特定的细胞类型。拟议的研究将为我们如何稳定处于这种幼稚状态的干细胞提供见解，提供更稳定的干细胞平台，用作药物发现计划和再生医学应用中的研究工具。我们的研究小组在干细胞生物学方面有着良好的记录，并拥有成功完成这一重要项目所需的专业知识。此外，在剑桥干细胞研究所工作使我们处于战略上的有利地位，与包括Kevin Chalut博士在内的密切合作者。一位多能性和分化的物理生物学专家，与我的实验室一起开发了一种新的水凝胶方案（手稿正在准备中），支持幼稚多能干细胞自我复制。这可能证明是一个非常有用的工具，在我们的目标，以产生天真的多能干细胞的印记错误免费

项目成果

Auxin-degron system identifies immediate mechanisms of Oct4

生长素-降解决定子系统识别 Oct4 的直接机制

• DOI: 10.1101/2020.09.21.306241
• 发表时间: 2020
• 作者: Bates L

Long-Term Perfusion Culture of Monoclonal Embryonic Stem Cells in 3D Hydrogel Beads for Continuous Optical Analysis of Differentiation

• DOI: 10.1002/smll.201804576
• 发表时间: 2019-02-01
• 期刊: SMALL
• 影响因子: 13.3
• 作者: Kleine-Bruggeney, Hans;van Vliet, Liisa D.;Hollfelder, Florian
• 通讯作者: Hollfelder, Florian

StemBond hydrogels control the mechanical microenvironment for pluripotent stem cells.

• DOI: 10.1038/s41467-021-26236-5
• 发表时间: 2021-10-21
• 期刊: Nature communications
• 影响因子: 16.6
• 作者: Labouesse C;Tan BX;Agley CC;Hofer M;Winkel AK;Stirparo GG;Stuart HT;Verstreken CM;Mulas C;Mansfield W;Bertone P;Franze K;Silva JCR;Chalut KJ
• 通讯作者: Chalut KJ

Auxin-degron system identifies immediate mechanisms of OCT4.

• DOI: 10.1016/j.stemcr.2021.05.016
• 发表时间: 2021-07-13
• 期刊: Stem cell reports
• 影响因子: 5.9
• 作者: Bates LE;Alves MRP;Silva JCR
• 通讯作者: Silva JCR

StemBond hydrogels optimise the mechanical microenvironment for embryonic stem cells

StemBond 水凝胶优化胚胎干细胞的机械微环境

• DOI: 10.1101/768762
• 发表时间: 2019
• 作者: Labouesse C