Three-dimensional folding and functional organization principles of the Drosophila genome. Drosophila melanogaster

Chromosomes are the physical realization of genetic information and thus form the basis for its reading, hindering and propagation. Here we present a high-resolution chromosomal contact map derived from a new genome-wide chromosome conformation capture approach (a simplified version of the Hi-C method) applied to Drosophila embryonic nuclei. The data show that the entire genome is linearly partitioned into well-demarcated physical domains that overlap extensively with active and repressive epigenetic marks. Chromosomal contacts are hierarchically organized between domains. Global modeling of compaction and clustering of domains show that inactive domains are condensed and confined to their chromosomal territories, while active domains reach out of the territory to form remote intra- and inter-chromosomal contacts. Overall design: One pilot sample, comprising seven paired-end Illumina GA-II lanes; one deep-sequenced sample, comprising seven paired-end Illumina HiSeq lanes

染色体是遗传信息的物质载体，因此构成了其读取、阻滞与传递的基础。本研究报道了一套高分辨率染色体相互作用图谱，该图谱基于一种全新的全基因组染色体构象捕获技术（Hi-C方法的简化版本）制备，应用对象为果蝇（Drosophila）胚胎细胞核。研究数据显示，全基因组以线性方式被划分为边界清晰的物理结构域，此类结构域与激活型及抑制型表观遗传标记存在广泛重叠。染色体间的相互作用在结构域之间呈现层级化的组织模式。通过对结构域折叠与聚集情况开展全局建模分析，研究发现非激活型结构域处于压缩状态并被限制在其染色体领地内，而激活型结构域则会突破领地边界，形成远距离的染色体内及染色体间相互作用。实验整体设计：1份预实验样本，包含7个双端测序的Illumina GA-II测序通道；1份深度测序样本，包含7个双端测序的Illumina HiSeq测序通道