Epigenetic Regulation of Germ Cell Derivation from heSCs

heSC 生殖细胞衍生的表观遗传调控

基本信息

批准号：
8379982
负责人：
Amander Clark
金额：
$ 33.96万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-08-01 至 2014-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8379982
关键词：
Address Animals Arabidopsis Binding Biological Assay Biology Caenorhabditis elegans Cell Differentiation process Cell Lineage Cells Chromatin Clinical Complex Congenital Abnormality DNA Methylation Data Derivation procedure Development EZH2 gene Ectoderm Embryo Embryonic Development Enzymes Epiblast Epigenetic Process Equilibrium Event Family Female First Pregnancy Trimester Gametogenesis Genes Genetic Genetic Transcription Germ Cells Germ Lines Germ cell tumor Goals Haploidy Hematopoietic Heterochromatin Histone H3 Histones Homeobox Genes Human Image In Vitro Infertility Laboratories Life Light Lysine Maintenance Methylation Modeling Mus Outcome Pathogenesis Pathway interactions Plants Polycomb Postdoctoral Fellow Proteins Regulation Research Role Somatic Cell Structure of primordial sex cell Testis Therapeutic Time Transcriptional Regulation Transplantation UC06 Undifferentiated Work X Chromosome X Inactivation base cell transformation chromatin modification clinically relevant gastrulation gene repression genome-wide human embryonic stem cell human embryonic stem cell line imprint in vivo insight pluripotency programs promoter relating to nervous system small hairpin RNA tool tumorigenesis

项目摘要

The goal of this project is to define the genetic and epigenetic signature that distinguishes human primordial germ cells (PGCs) from human embryonic stem cells (hESCs) with a specific focus on trimethylation (me3) of histone H3 lysine (K) 27, and function of the Polycomb Group (PcG) proteins on PGC formation. Human ESCs are the only genetically malleable human cell-based model for examining human germ cell formation. Germ cell derivation from the epiblast requires a delicate balance involving expression of pluripotent genes (such as NANOG and OCT4), suppression of somatic genes (such as HOXB1 and BRACHYURY) and functional unipotency to exclusively form gametes. Loss of germ line unipotency results in germ cell tumorigenesis. Therefore, disruption of the balance of factors that regulate germ cell derivation results in adverse clinical outcomes. In previous work Dr. Clark has shown that derivation of human germ cells from hESCs varies between independently derived lines. Her preliminary data now reveals that this can be correlated with differences in transcription of germ cell specific genes in undifferentiated ESCs as well as differential methylation of H3K27me3 at promoters of germ cell-expressed loci. In this Project, Dr Clark will continue her research on the role of the PcG proteins and H3K27me3 in modulating PGC formation in the following specific Aims: 1) Evaluating H3K27me3 and X reactivation during PGC development in two lines of female hESCs; 2) Deciphering the genome wide localization of H3K27me3 in four lines of hESCs, and PGCs derived from hESCs, and 3) Determining the function of the PcG repressive complex (PCR2) in PGC formation in four independently derived lines of hESCs. Sharing results on germ cell formation from hESCs with Projects 1 and 3 are essential to understanding hESC potential because the ability to form germ line is simultaneously reversed to form neural and hematopoietic lineages (loss of pluripotency and activation of somatic cell transcriptional programs). Thus identification of hESC lines that are capable of both faithful germ cell formation and robust somatic cell differentiation would constitute the best developmental models and therapeutic tools for future research.

该项目的目标是定义区分人类原始特征的遗传和表观遗传特征来自人胚胎干细胞 (hESC) 的生殖细胞 (PGC)，特别关注三甲基化 (me3) 组蛋白 H3 赖氨酸 (K) 27 的变化，以及 Polycomb Group (PcG) 蛋白对 PGC 形成的功能。人类 ESC 是唯一一种基于遗传可塑性的人类细胞模型，用于检查人类生殖细胞的形成。从外胚层衍生的生殖细胞需要涉及多能基因表达的微妙平衡（如NANOG和OCT4），抑制体细胞基因（如HOXB1和BRACHYURY）和功能单能，专门形成配子。生殖系单能性丧失导致生殖细胞肿瘤发生。因此，调节生殖细胞衍生的因素平衡被破坏会导致不良的临床结果。克拉克博士在之前的工作中表明，人类生殖细胞源自 hESCs 在独立衍生的细胞系之间存在差异。她的初步数据现在表明这可以是与未分化 ESC 中生殖细胞特异性基因转录的差异相关 H3K27me3 在生殖细胞表达基因座启动子处的差异甲基化。在这个项目中，克拉克博士将继续研究 PcG 蛋白和 H3K27me3 在调节 PGC 形成中的作用以下具体目标：1) 评估两个品系的 PGC 发育过程中的 H3K27me3 和 X 重新激活雌性 hESC； 2) 破译 H3K27me3 在四个 hESC 和 PGC 系中的全基因组定位源自 hESC，以及 3) 确定 PGC 中 PcG 抑制复合物 (PCR2) 的功能四个独立衍生的 hESC 系的形成。分享 hESC 生殖细胞形成的结果项目 1 和 3 对于了解 hESC 潜力至关重要，因为形成种系的能力同时逆转形成神经和造血谱系（多能性丧失和多能性激活体细胞转录程序）。因此鉴定出能够忠实地表达生殖细胞形成和强大的体细胞分化将构成最好的发育模型以及未来研究的治疗工具。