Comprehensive Characterization of Heterochromatin Domains

项目总结/摘要 异染色质是一种基因组结构，在所有真核生物中起作用，以确定细胞身份并维持细胞的完整性。 通过沉默基因来稳定基因组异染色质组装的要求是并入 具有组蛋白修饰活性的沉默蛋白复合物的染色质，其导致抑制的基因 表情这种一般机制在所有真核生物中是保守的，尽管有多种多样的真核生物。 异染色质结构域存在，甚至在同一生物体内。我们已经知道很多因素， 虽然这些蛋白质对异染色质有贡献，但对特定途径中的许多关键事件知之甚少。一个挑战 在研究异染色质中，一个重要的事实是，在体内操纵中心成分往往会影响多个异染色质。 异染色质的类型或细胞中的其他相关途径。本项目的目标将解决这一问题 问题从三个方面：首先，通过使用功能性的体外重构异染色质系统， 了解异染色质沉默在一个孤立的环境中的机制。其次，使用预- 组装异染色质结构域，以确定细胞内有助于异染色质的新因子 形成和维持。第三，通过建立制度，解决具体的非编码贡献 RNA元件启动和维持异染色质。 异染色质酵母模型的初步研究将为异染色质的研究领域做出重要贡献。 染色质生物学，也将作为一个模型，为后续的研究，在人类系统进行 在转型为独立调查员之后。该项目的主要目标是全面 表征异染色质结构域，以比较基因的核心保守特征， 沉默和基因组稳定性。人类异染色质结构域的多样性是显而易见的，然而， 控制这些结构域组装的原理与芽殖和分裂酵母中的原理非常相似 模型这些基本的相似性使得将酵母研究的结果与人类进行比较成为可能， 使用在简单的酵母模型中开发的方法作为研究人类的指南， 异染色质这个主题是这个提议的基础，也是我过渡到 独立

PROJECT SUMMARY/ABSTRACT Heterochromatin is a genomic structure that functions in all eukaryotes to determine cell identity and maintain genome stability by silencing genes. The requirements for heterochromatin assembly are incorporation into chromatin of silencing protein complexes with histone modification activity that lead to repressed gene expression. This general mechanism is conserved in all eukaryotes, though multiple varieties of heterochromatic domains exist, even within the same organism. Much is known about the factors that contribute to heterochromatin, yet many key events in specific pathways are poorly understood. One challenge in studying heterochromatin is the fact that manipulation of the central components in vivo often affects multiple types of heterochromatin or other related pathways in the cell. The aims of this project will address this problem in three ways: firstly, by using a functional in vitro reconstituted heterochromatin system to better understand the mechanism of heterochromatic silencing in an isolated environment. Secondly, using a pre- assembled heterochromatin domain to identify new factors within the cell that contribute to heterochromatin formation and maintenance. Third, by establishing a system to address the contribution of specific non-coding RNA elements to initiation and maintenance of heterochromatin. Initial studies in yeast models of heterochromatin will make important contributions to the field of chromatin biology and will also serve as a model for subsequent studies in the human system to be carried out after the transition to independent investigator. The primary goal of the project is to comprehensively characterize heterochromatin domains in order to compare conserved features that are central to gene silencing and genome stability. The diversity of human heterochromatic domains is evident, yet the general principles that govern assembly of these domains remain quite similar to those in the budding and fission yeast models. These basic similarities make it feasible to compare results of yeast studies to humans and also to use the approaches that have been developed in the simpler yeast models as a guide to study human heterochromatin. This theme is the foundation of this proposal and the direction I will take as I transition to independence.