Chromatin Structure and Genome Response in Maize

玉米染色质结构与基因组响应。PI: Henry W. Bass（佛罗里达州立大学）共同PI: Jonathan H. Dennis（佛罗里达州立大学），Karen M. McGinnis（佛罗里达州立大学）和Oghenekome U. Onokpise（佛罗里达农业和机械大学）了解基因组如何在功能上组织是生物学的主要挑战。在结构上，真核生物（如植物、动物或真菌）的基因组被组织成染色质，染色质是DNA和相关蛋白质的复合体。染色质的基本亚基是核小体，由约150个碱基对的DNA包裹着8个组蛋白组成。众所周知，基因组中的核小体位置随着基因表达水平的变化而变化。然而，基因组结构与基因表达之间的具体关系尚未明确。该项目的总体目标是表征玉米基因组的染色质结构与功能的关系，特别是关于核小体占用和基因表达。该研究使用计算、生化、遗传和微观方法来实现三个特定目标：(1)DNA微阵列将用于全基因组染色质结构的研究。在这一过程中，新的预测工具将从人类基因组研究的技术中适应于玉米基因组，(2)将研究一种名为mop1的突变体的基因组变化，该突变体被认为通过小rna和沉默潜在有害的基因组变化来调节染色质结构；(3)利用3D分子细胞学技术对正常植物和mop1突变体的染色质结构进行可视化。该项目将提供玉米基因组中核小体占用位置的图和研究染色质结构的新工具。此外，定制微阵列将可用于更广泛的植物基因组学社区。所有数据将发布给GenBank，并可在项目网站（www.maizenucleosome.org）和公共数据库（www.maizegdb.org、www.gramene.org和www.maizesequence.org）上获取。不同的学生直接参与实地和实验室活动将提供培训机会，并接触到植物遗传学和基因组研究。该项目将继续通过玉米-10- maze染色体图谱领域为公众开展独特的外展活动：10条玉米染色体中的每一条都按比例显示为单行，并在适当的地图位置显示突变体。这个真实大小的玉米染色体视图提供了对基因组组织的切实理解，并吸引参与者讨论基因组学研究对应对社会挑战的重要性。

Chromatin Structure and Genome Response in Maize.PI: Henry W. Bass (Florida State University)Co-PI(s): Jonathan H. Dennis (Florida State University), Karen M. McGinnis (Florida State University) and Oghenekome U. Onokpise (Florida Agricultural and Mechanical University) Understanding how genomes are organized functionally is a major challenge in biology. Structurally, the genomes of eukaryotes, such as plants, animals or fungi, are organized into chromatin, which is a complex of DNA and associated proteins. The basic subunit of chromatin is the nucleosome, comprising ~150 base pairs of DNA wrapped around eight histone proteins. It is known that nucleosome positions in the genome vary with changes in gene expression levels. However, the specific relationship between genome structure and gene expression has not been clearly defined. The overall goal of this project is to characterize the chromatin structure of the maize genome in relation to function, specifically with respect to nucleosome occupancy and gene expression. The research uses computational, biochemical, genetic, and microscopic methods to accomplish three specific objectives: (1)DNA microarrays will be developed for genome-wide studies of chromatin structure. In the process new predictive tools will be adapted to the maize genome from technology developed for study of the human genome, (2) genome changes will be investigated in a mutant called mop1, which is thought to regulate chromatin structure through small RNAs and by silencing potentially deleterious genome changes; and (3) chromatin structure of normal plants and mop1 mutants will be visualized using 3D molecular cytology. The project will deliver plots that map sites of nucleosome occupancy in the maize genome and new tools for investigation of chromatin structure. In addition, custom microarrays will be available for use by the broader plant genomics community. All data will be released to GenBank and will be available on the project website (www.maizenucleosome.org) and on public databases including www.maizegdb.org, www.gramene.org, and www.maizesequence.org. Direct involvement of diverse students in field and laboratory activities will provide training opportunities and exposure to plant genetics and genomic research. The project will continue a unique outreach activity for the public through a Maize-10-Maze chromosome-map field: each of the ten maize chromosomes is displayed as a single row to scale and with mutants in appropriate map positions. This life-size view of the maize chromosomes provides a tangible understanding of genome organization and engages participants in discussion about the importance of genomics research to meet societal challenges.