基于“组蛋白密码”假设,以黑腹果蝇(Drosophila melanogaster)为研究对象,应用CoSBI(coherent and shifted bicluster identification)算法对黑腹果蝇Oregon-R细胞株培养14-16h的胚胎细胞,在全基因组范围、RNA聚合酶Ⅱ结合区域、绝缘子结合蛋白的结合区域的22种组蛋白修饰的分布情况进行CoSBI聚类分析,发现了果蝇基因组的功能区域所具有的一些“核心组蛋白修饰”,说明果蝇基因组的组蛋白修饰具有成簇出现、相互协同的调控模式.另外,将黑腹果蝇处于14-16h胚胎细胞的基因分为表达与不表达两类,分析了两类基因所在区域组蛋白修饰的组合模式.
Based on histone code hypothesis, a scalable subspace clustering algorithm, coherent and shifted bicluster identification (CoSBI) is applied to analyze the distribution features of histone modifications in order to study its regulational function in the biological processes. Genome-wide maps of 22 histone modifications have been generated using ChIP-seq of 14-16h embryos for Ore- gon-R strain of Drosophila rnelanogasters. Considering the distribution of 22 histone modifications on the whole genome, genomic regions binding by RNA polymerase Ⅱ and seven distinct insulators binding proteins, a significant correlation feature is analyzed between histone modifications and some core combinatorial patterns are found out. Furthermore, the algorithm is applied on two groups with different activities (expressed genes and non-expressed genes) respectively and combinational pat- terns of histone modifications associated with gene expression level are analyzed.