Epigenetic mechanisms governing genome partitioning and gene expression in germ cells

三维基因组组织，其中线性DNA序列被分割成 功能不同的区域，对于在每个细胞中精确地部署遗传信息是必不可少的 打字。最近，越来越多的破坏性疾病和疾病被归因于 基因组组织的破坏，然而其机制基础仍然鲜为人知， 尤其是在活体内。尤其是结合因子和序列元件的活性如何被翻译成 表观遗传状态和控制基因表达残基的三维基因组结构域 很神秘。线虫的种系在体内提供了相关的和实验上有利的 用配位技术剖析基因组结构域正确建立机制的模型 监管。在这个系统中，我们研究了不同的大规模基因调控机制 PiRNA的生物发生，X染色体调控，以及从生殖系到体细胞命运的转变。 我们最近开发了可靠地提纯生殖核的能力，提纯的数量足以满足基因组 分析，包括芯片序列分析、RNA-序列分析和染色质捕获构象分析。这一成就 消除了该领域的一个主要障碍，以剖析生殖系中的基因表达机制。有了这个 新的能力，我们现在将描述野生动物的基本转录和表观遗传机制 具有前所未有的特异性的类型生殖核。使用这些数据，我们现在将定义关键机制 控制种系到胞体的转化，基因组的协调、种系特异性调节 包含数千个piRNA基因的结构域，以及X染色体的时间和全球调节 基因在生殖系中的表达。拟议中的实验的成功完成将说明 对大规模基因组组织的体内机制知之甚少但至关重要的机制 影响基因表达，反之亦然。

Three-dimensional genome organization, in which the linear DNA sequence is partitioned into functionally distinct domains, is essential for the precise deployment of genetic information in every cell type. An increasing number of devastating disorders and diseases have recently been attributed to disruption of genome organization, yet the mechanistic underpinnings remain poorly understood, especially in vivo. In particular, how the activity of binding factors and sequence elements is translated to epigenetic states and three-dimensional genomic domains to govern gene expression remains mysterious. The germ line of C. elegans provides a relevant and experimentally advantageous in vivo model to dissect the mechanisms governing proper establishment of genomic domains with coordinated regulation. In this system, we investigate diverse large-scale gene regulatory mechanisms controlling piRNA biogenesis, X chromosome regulation, and transformation from the germline to the somatic fate. We have recently developed the ability to reliably purify germ nuclei at quantities sufficient for genomic analyses, including ChIP-seq, RNA-seq, and chromatin capture conformation assays. This achievement removes a major barrier in the field to dissect gene expression mechanisms in the germ line. With this new capacity, we will now characterize fundamental transcriptional and epigenetic mechanisms in wild type germ nuclei with unprecedented specificity. Using these data, we will now define key mechanisms governing the germline-to-soma transformation, the coordinated, germline-specific regulation of genomic domains containing thousands of piRNA genes, and the temporal and global regulation of X chromosome gene expression in the germ line. The successful completion of the proposed experiments will illuminate the poorly understood yet vitally important in vivo mechanisms by which large-scale genome organization influences gene expression, and vice versa.