Function of Kdm4dl-mediated heterochromatin removal in the preimplantation mouse embryo

Kdm4dl 介导的植入前小鼠胚胎异染色质去除的功能

基本信息

批准号：
10540694
负责人：
Sean Shadle
金额：
$ 7.18万
依托单位：
UNIVERSITY OF UTAH
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-01 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10540694
关键词：
Ablation Address Affect Animals Area Assisted Reproductive Technology Auxins Biological Assay Cancer Biology Cell Line Cell Nucleus Cells Chimera organism Chromatin Chromatin Modeling Code Complement Data Deposition Development Developmental Process Doxycycline Embryo Embryonic Development Environment Epigenetic Process Excision Fertility Fertilization Gene Activation Gene Expression Gene Expression Regulation Genes Genetic Epistasis Genetic Transcription Genome Goals Health Heterochromatin Histones Human Immunofluorescence Immunologic Knock-out Knockout Mice Lysine Mediating Methylation Modeling Mus Orthologous Gene Pathway interactions Pattern Phenotype Placenta Pre-implantation Embryo Development Process Productivity Proteins Research Personnel Research Project Grants Role System Testing Time Totipotency Totipotent Training Transcript Transcriptional Activation Transgenes Untranslated RNA blastocyst blastomere structure chromatin remodeling demethylation egg embryo cell embryonic stem cell histone demethylase histone modification in vivo innovation mouse model novel overexpression placental mammal preimplantation programs protein expression transcription factor transcriptome sequencing zygote

项目摘要

PROJECT ABSTRACT This project will investigate the function of a currently unstudied histone demethylase, Kdm4dl, in the mouse preimplantation embryo. Many others have shown the developmental importance of activating genes and repeat sequences during a process known as Embryonic Genome Activation (EGA), the moment when the embryo switches on transcription for the first time. EGA involves activation of both protein coding genes as well as repeat sequences that are critical for remodeling the chromatin environment of the early embryo. Yet, even with its known developmental importance, the factors which facilitate EGA are still largely unknown. Here, for the first time, I will investigate the importance of Kdm4dl, which catalytically removes the repressive histone modification H3 Lysine 9 tri-methylation (H3K9me3), in early mouse embryogenesis. I hypothesize that Kdm4dl is required for reprogramming the nuclei of the preimplantation embryo by removing repressive H3K9me3, which facilitates strong activation of EGA-associated transcripts. In line with this hypothesis, my preliminary data demonstrate temporally coordinated Kdm4dl protein expression during the 2-cell stage, when EGA occurs. Moreover, Kdm4dl over-expression is sufficient to demethylate H3K9me3 in embryonic stem cells leading to strong activation of EGA-associate transcripts and repeats. Combined, these preliminary data provide further support for pursuing the project’s hypothesis further. The two outstanding questions I aim to address are: 1. Is Kdm4dl expression sufficient to reprogram cells to a state of expanded potential, consistent with a 2-cell-like totipotent state? and 2. Is Kdm4dl expression necessary for H3K9 demethylation and activation of EGA-associated genes and repeats in vivo? To aid in addressing these questions, I have developed both an innovative embryonic stem cell system which recapitulates the temporal dynamics of Kdm4dl expression in the preimplantation embryo, and I have also established a Kdm4dl knockout mouse model. This research project, combined with my detailed training plan, is consistent with my technical and professional goals of becoming an independent academic investigator studying chromatin dynamics in the early mammalian embryo, with relevance to human fertility.

项目摘要该项目将研究目前尚未研究的组蛋白去甲基化酶 Kdm4dl 在许多其他研究表明激活基因对小鼠植入前胚胎的发育至关重要。并在称为胚胎基因组激活（EGA）的过程中重复序列，即胚胎第一次开启转录也涉及到两个蛋白质编码基因的激活。然而，对于重塑早期胚胎的染色质环境至关重要的重复序列。尽管其对发育的重要性已为人所知，但促进 EGA 的因素仍然很大程度上未知。第一次，我将研究 Kdm4dl 的重要性，它可以催化去除抑制性组蛋白小鼠早期胚胎发生中的 H3 赖氨酸 9 三甲基化 (H3K9me3) 修饰。是通过去除抑制性 H3K9me3 来重新编程植入前胚胎的细胞核所必需的，这促进了 EGA 相关转录本的强烈激活，我的初步假设与此一致。数据表明，在 2 细胞阶段，当 EGA 此外，Kdm4dl 过度表达足以使胚胎干细胞中的 H3K9me3 去甲基化。这些初步数据结合起来，导致 EGA 相关转录本和重复序列的强烈激活。为进一步研究该项目的假设提供进一步的支持，这是我想要解决的两个悬而未决的问题。地址是： 1. Kdm4dl 表达是否足以将细胞重编程至扩展潜力的状态，一致具有 2 细胞样全能状态？ 2. Kdm4dl 表达对于 H3K9 去甲基化是必需的吗？ EGA 相关基因的激活和体内重复？为了帮助解决这些问题，我有开发了一种创新的胚胎干细胞系统，该系统概括了时间动态 Kdm4dl在植入前胚胎中表达，我还建立了Kdm4dl敲除小鼠这个研究项目，结合我详细的训练计划，与我的技术和能力是一致的。成为研究染色质动力学的独立学术研究者的职业目标早期哺乳动物胚胎，与人类生育能力相关。