Gene Expression in the Preimplantation Mouse Embryo

植入前小鼠胚胎中的基因表达

• 批准号: 7936524
• 负责人: RICHARD M SCHULTZ
• 金额: $ 29.28万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7936524
• 关键词: Assisted Reproductive Technology; Attention; Binding; Binding Proteins; Candidate Disease Gene; Cell physiology; Cells; Chromatin; Chromatin Structure; Competence; DNA; Development; Embryo; Embryonic Development; Enzymes; Family; Fertilization; Fostering; Funding; Gene Expression; Gene Expression Regulation; Genes; Genetic Transcription; Genome; Goals; Grant; Growth; Histone H3; Histones; Human; Human Development; Infertility; Knowledge; Link; Mediating; Meiosis; MicroRNAs; Molecular; Morula; Mus; Oocytes; Participant; Pattern; Phase; Post-Transcriptional Regulation; Pre-implantation Embryo Development; Process; Prophase; RNA Interference; Recruitment Activity; Research Personnel; Role; Series; Staging; Testing; Transcript; Transferase; Transgenic Organisms; Ubiquitin; blastocyst; egg; embryo stage 2; helper-dependent adenoviral vector; heterochromatin-specific nonhistone chromosomal protein HP-1; improved; mRNA Transcript Degradation; member; oocyte maturation; preimplantation; programs; research study; therapy development; transcription factor; zygote

DESCRIPTION (provided by applicant): The long-term goal of this application is to determine underlying mechanisms that govern changes in gene expression during oocyte growth and the maternal-to-zygotic transition, both of which are linked and essential for development. A universal feature of oocyte development is that transcription declines commencing around mid-growth such that fully-grown oocytes are essentially transcriptionally quiescent. In mouse, this decline correlates with visible changes in chromatin structure, which becomes more condensed and decreased activity of the transcription machinery. Using a transgenic RNAi approach that permits study of the function of any gene in oocyte development, Specific Aim 1 will test the hypothesis that members of the HP1 family of chromatin-binding proteins and UBC9, via its central role in sumoylation, are essential for changes in chromatin structure and transcriptional activity that occur during oocyte growth. A major reprogramming of gene expression is first detected during the 2-cell stage and essential for continued development. Superimposed on genome activation is development of a chromatin-mediated transcriptionally repressive state. Our transcript profiling experiments identified Myc as a candidate gene pivotal for genome activation and reprogramming of gene expression, and Hdad as essential for establishing the transcriptionally repressive state. Using an RNAi approach to target Myc and Hdad, Specific Aim 2 will test the hypothesis that Myc and Hdad are critical for these two processes that collaboratively sculpt the appropriate pattern of gene expression required for successful development following genome activation. Oocytes express miRNAs and mRNA degradation, which initiates during oocyte maturation and continues during early preimplantation development, is a post-transcriptional mechanism that contributes to determining the global pattern of gene expression in the embryo. Specific Aim 3 will test the hypothesis that miRNAs target specific mRNAs for degradation in P-bodies and that this mechanism is essential for proper oocyte/embryo development. The proposed studies will increase our basic knowledge and understanding of human development. In the near term, they may help improve treatment of human infertility by providing new knowledge that will facilitate the rational development of treatments that foster improved oocyte and preimplantation embryo development in the practice of Assisted Reproductive Technology (ART).

描述（由申请人提供）：本申请的长期目标是确定控制卵母细胞生长和母体向合子转变期间基因表达变化的潜在机制，这两者对于发育都是相关且必不可少的。卵母细胞发育的一个普遍特征是转录从生长中期开始下降，因此完全生长的卵母细胞基本上处于转录静止状态。在小鼠中，这种下降与染色质结构的明显变化相关，染色质结构变得更加浓缩，转录机制的活性降低。使用转基因RNAi方法，可以研究卵母细胞发育中任何基因的功能，Specific Aim 1将测试这样的假设：染色质结合蛋白HP1家族的成员和UBC9，通过其在苏酰化中的核心作用，对于卵母细胞生长过程中发生的染色质结构和转录活性的变化至关重要。基因表达的主要重编程首先在 2 细胞阶段被检测到，这对于持续发育至关重要。叠加在基因组激活上的是染色质介导的转录抑制状态的发展。我们的转录本分析实验确定了 Myc 作为基因组激活和基因表达重编程的关键候选基因，而 Hdad 对于建立转录抑制状态至关重要。 Specific Aim 2 使用 RNAi 方法来靶向 Myc 和 Hdad，将测试这样的假设：Myc 和 Hdad 对于这两个过程至关重要，这两个过程共同塑造基因组激活后成功发育所需的适当基因表达模式。卵母细胞表达 miRNA 和 mRNA 降解，这种降解在卵母细胞成熟期间开始，并在早期植入前发育过程中持续，是一种转录后机制，有助于确定胚胎中基因表达的整体模式。具体目标 3 将测试以下假设：miRNA 靶向特定 mRNA，以便在 P 体中降解，并且这种机制对于卵母细胞/胚胎的正常发育至关重要。拟议的研究将增加我们对人类发展的基础知识和理解。在短期内，它们可能通过提供新的知识来帮助改善人类不孕不育的治疗，这些新的知识将促进在辅助生殖技术（ART）实践中促进改善卵母细胞和植入前胚胎发育的治疗方法的合理开发。