Chromatin profiling of dREAM and dNuRD complexes

染色质结构的调节在细胞的分化、增殖和恶性转化过程中起着至关重要的作用。已经确定了几个染色质调节蛋白复合体，但我们对它们如何合作知之甚少。DREAM和dNuRD是高度保守的多亚单位蛋白质复合体。人类DREAM和dNuRD亚基的同源物，如视网膜母细胞瘤肿瘤抑制基因pRb和转移相关蛋白MTA1-3，在癌症中被解除调控。在线虫中，这两个复合体协同调节发育过程中细胞命运的决定。Dream和dNuRD都被认为通过作用于染色质结构来抑制转录。在这里，我们建议使用新的基于微阵列的方法(ChlP-on-Chip，DamID，RNAi/微阵列)来确定DREAM和dNuRD的基因组结合模式和靶基因。我们的目标是识别和鉴定这两个复合体共同调节的基因，并揭示组蛋白修饰模式在DREAM和dNuRD介导的基因抑制中的作用。通过这种系统生物学的方法，我们希望了解在多细胞生物体的发育过程中，不同染色质调节复合体的作用是如何协调的，以影响转录程序的准确执行。

Regulation of chromatin structure is of fundamental importance during differentiation, proliferation and malignant transformation of cells. Several chromatin regulating protein complexes have been identified but we know little about how they cooperate. dREAM and dNuRD are highly conserved multisubunit protein complexes. Human homologs of dREAM and dNuRD subunits, such as the Retinoblastoma tumour suppressor pRb and the metastasis- associated proteins MTA1-3, are deregulated in cancer. In C.elegans both complexes cooperate to regulate cell fate determination during development. Both, dREAM and dNuRD are thought to repress transcription by acting on chromatin structure. Here, we propose to use novel microarray based methods (ChlP-on-chip, DamID, RNAi/microarray) to determine genome wide binding patterns and target genes of dREAM and dNuRD. We aim to identify and characterize genes coregulated by both complexes and to reveal the role of histone modification patterns in dREAM and dNuRD mediated gene repression. With this systems biology approach, we are hoping to learn how the action of different chromatin regulating complexes is orchestrated to effect the precise execution of transcriptional programmes during the development of multicellular organisms.