Chromatin Charting: Organization and Dynamics of Plant Nuclear DNA in situ

细胞核是真核细胞内的大部分基因组信息被组织在其中的亚细胞器。尽管在过去的几年里，生物体基因组测序取得了巨大的进步，但这些大量的遗传信息在植物和动物细胞核中的存储和物理操作方式仍然是一个谜。从使用杂交技术和显微镜工作的研究，一个有组织的亚核结构的图片已经出现。一个主要的亚核结构是染色体，它包含生物体的基因组。 最近，应用绿色荧光蛋白（GFP）作为染色体物质的体内标记，已经允许在动物和真菌的活细胞中观察染色体。该项目的目标是扩展GFP技术，通过使用完整植物中的细胞绘制每个染色体上特定基因的相对物理位置来了解亚核结构。为了实现可视化和绘制模型植物所有染色体上的基因的目的，拟南芥、GFP和该蛋白质的两种不同颜色变体（黄色[YFP]和蓝色[BFP]）将用作转基因植物中的体内标签。使用这三个不同的标记，基因组的物理组织的基因表达和基因动员模式的特点。 该项目是将该技术建立为可视化基因组组织和基因表达之间关系的强大工具的第一步。 虽然它正在模式植物拟南芥中进行测试，但这种方法应该提供必要的资源和工具来解决所有植物中有关亚核结构和染色质动态的基本问题。此外，从这项工作的见解应该有助于我们了解全球基因调控以及表观遗传现象在所有真核生物。

The nucleus is the subcellular organelle in which the bulk of the genomic information within an eukaryotic cell is organized. Although tremendous advances in sequencing genomes of organisms have taken place in the past few years, the way by which this vast amount of genetic information is stored and physically manipulated in the nuclei of plants and animals remains a mystery. From studies using hybridization technologies and microscopy work, a picture of an organized subnuclear structure has emerged. One major subnuclear structure is the chromosomes, which contain the genome of an organism. More recently, the application of the Green Fluorescent Protein (GFP) as an in vivo tag of chromosomal substances has allowed the visualization of chromosomes in live cells of animals and fungi. The goal for this project is to extend the GFP technology to understand subnuclear architecture by charting the relative physical position of specific genes on each of the chromosomes using cells within an intact plant. To achieve the objective of visualizing and charting the genes on all the chromosomes of a model plant, Arabidopsis, GFP and two different color variants (yellow [YFP] and blue [BFP]) of this protein will be used as in vivo tags in transgenic plants. Using the three distinct markers, the physical organization of the genome in relation to gene expression and gene mobilization patterns will be characterized. The project is a first step to establish this technology as a powerful tool to visualize the relationship between the genome organization and gene expression. While it is being tested in a model plant, Arabidopsis, this approach should provide the necessary resources and tools to address fundamental questions about subnuclear architecture and chromatin dynamics in all plants. Further, insights from this work should contribute to our understanding of global gene regulation as well as epigenetic phenomena in all eukaryotic organisms.