Epigenetic and developmental regulation of embryonic plasticity and gametogenesis

项目摘要/摘要：早期胚胎细胞是多能的，具有瞬时能力 产生一个有机体的所有细胞。发育生物学中的一个基本问题涉及识别 这种暂时性发育可塑性背后的表观遗传因素，以及理解 实现并保持对特定细胞谱系的承诺。胚胎多能性是如何建立起来的， 以及发育是否使细胞可塑性的限制与细胞命运的获得相协调 人们对此知之甚少。表观遗传现象指的是基因表达和染色质组织的变化 通过细胞分裂继承而不改变潜在的DNA序列。最近，我在学习期间 博士后研究发现，KEY的结合存在一种未被认可的发展规律 表观遗传信息的分子载体，复制偶联的组蛋白H3和组蛋白变异体H3.3， 在配子发生过程中，影响早期胚胎的表观遗传组织，对 多能性和血统承诺。 这项独立之路奖提案的目标是请求对培训的支持，以便 发展和应用基因组方法方面的专门知识，同时解决表观遗传调控的作用 胚胎发育早期的可塑性，以及细胞命运的维持。在此期间提供K99/R00支持 我职业生涯的阶段将对我作为一名独立研究员的成功发展起到变革性的作用。这个 本提案中概述的研究计划和职业发展将利用广泛的 资源，以及与领先的基因组学专家和 生物信息学。这项建议将研究表观遗传调控和早期发育的时机。 胚胎可塑性。具体地说，在该奖项的K99指导阶段，首席研究员(PI) 将结合当前的专业知识和约翰霍普金斯大学博士后培训期间产生的初步结果 大学，利用合作者实验室开发的新技术来回答 关于胚胎可塑性和细胞的动态表观遗传机制的基本问题 命运的限制。这一方法承诺解决以下具体目标1)确定发展 H3和H3.3双峰掺入在早期胚胎发生和配子发生中的意义 描述H3、H3.3的全基因组定位及其早期的翻译后修饰 胚胎发育及其对染色质可及性和基因表达的影响，以及3)描绘了 协调两类不同组蛋白基因发育调控的分子途径 对生育和细胞命运的限制很重要。这次培训的完成将会发展我的研究专长， 在描述胚胎可塑性的表观遗传调控的潜在机制时，这将是 适用于生殖生物学、胚胎学、细胞重编程、生育等领域。

Project Summary/Abstract: Early embryonic cells are pluripotent, possessing the transient capacity to generate all the cells of an organism. A fundamental question in developmental biology concerns identifying the epigenetic factors that underlie this temporary developmental plasticity, as well as understanding how commitment to a specific cell lineage is achieved and maintained. How embryonic pluripotency is established, and whether development coordinates the restriction of cellular plasticity with the acquisition of cell fate is poorly understood. Epigenetic phenomena refer to changes in gene expression and chromatin organization inherited through cell divisions without changing the underlying DNA sequences. Recently, studies during my postdoctoral research have uncovered an unappreciated developmental regulation of the incorporation of key molecular carriers of epigenetic information, the replication-coupled histone H3 and histone variant, H3.3, during gametogenesis that influences the epigenetic organization in the early embryo, with a lasting effect on pluripotency and lineage commitment. The goal of this Pathway to Independence Award proposal is to request support for training in order to develop expertise in, and to apply, genomic approaches while addressing the role of epigenetic regulation of plasticity during early embryonic development, as well as cell fate maintenance. K99/R00 support during this stage of my career will be transformative to my successful development as an independent researcher. The research plans and career development outlined in this proposal will take advantage of the extensive resources at Johns Hopkins University, as well as collaborate with leading experts in genomics and bioinformatics. This proposal will examine the epigenetic regulation and developmental timing of early embryonic plasticity. Specifically, during the K99 mentored phase of this award the principal investigator (PI) will combine current expertise and preliminary results generated during postdoctoral training at Johns Hopkins University, with newly developed techniques developed in the collaborator's laboratories to answer fundamental questions regarding the dynamic epigenetic mechanisms underlying embryonic plasticity and cell fate restriction. This approach promises to resolve the following specific aims 1) determine the developmental significance of H3 and H3.3 bimodal incorporation during early embryogenesis and gametogenesis, 2) characterize the genome-wide localization of H3, H3.3, and their post-translational modifications during early embryogenesis, as well as their influence on chromatin accessibility and gene expression and 3) delineate the molecular pathways that orchestrate the developmental regulation of two distinct classes of histone genes important for fertility and cell fate restriction. The completion of this training will develop my research expertise, while delineating the mechanisms underlying the epigenetic regulation of embryonic plasticity, which will be applicable to the fields of reproductive biology, embryology, cellular reprogramming, and fertility.