Functional Genomics of Maize Centromeres

玉米着丝粒的功能基因组学

• 批准号: 1444514
• 负责人: R Kelly Dawe
• 金额: $ 461.62万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1444514&HistoricalAwards=false
• 关键词: Functional; Genomics; Maize; Centromeres

PI: R. Kelly Dawe (University of Georgia-Athens) Co-PIs: James A. Birchler (University of Missouri-Columbia) and Jiming Jiang (University of Wisconsin-Madison) All plant genomes contain centromeres, structural regions that ensure chromosomes segregate properly during cell division. Centromeres are a challenge to study because they contain repetitive DNA sequences and few genes. The goal of this project is to develop an understanding of how the sequences in centromeres relate to their function, and how changes in centromere size or changes in a key centromere binding protein (CENH3) can alter the behavior of centromeres. In particular the project will study genetic crosses and mutants that can induce centromere failure and chromosome loss in hybrids. Chromosome loss induced by centromere modification can result in haploid plants, which are of great value to corn breeders, as they can rapidly accelerate the production of new inbred lines. It is anticipated that the information and technology generated will have direct applications to agriculture - not only in maize but all other crops that utilize haploids as a breeding tool. With regards to training and outreach, the project will provide research training for undergraduate and graduate students as well as postdoctoral fellows in plant genomics and biotechnology. In addition, a series of training workshops will be held to disseminate techniques and materials generated in this project. All project outcomes will be made available to the research community through a dedicated project web site and through dissemination by long-term repositories that include NCBI, MaizeGDB and Gramene. The overall goals of the project are to understand the genetic and epigenetic components of maize centromeres and to reveal the role of centromere size in uniparental chromosome elimination which leads to haploid formation. The specific objectives are to: 1) determine whether common centromere repeat sequences are sufficient to induce centromere function using novel chromosome painting probes, chromosome visualization tools that dramatically improve the ability to detect changes in chromosome structure; 2) determine how a suite of chromatin markers are affected by changes in centromere size and location using maize chromosomes transferred into oat as well as B chromosomes that have undergone a cycle of inactivation and reactivation; 3) test whether centromere size disparity can cause uniparental genome elimination by screening lines with centromeres whose size have been modified by manipulating genome size, and by using cenh3 mutants with specialized transgenes; and 4) determine how maize centromeres behave in situations of uniparental genome elimination, particularly in wheat X maize and oat X maize crosses that are regularly used in haploid breeding schemes.

PI：R。KellyDawe（佐治亚大学 - 琼斯大学）Co-Pis：James A. Birchler（密苏里州 - 哥伦比亚大学）和Jiming Jiang（威斯康星大学麦迪逊分校）所有植物基因组都含有共感，这些植物基因组都有结构性区域，可确保在细胞分裂期间适当地分离染色体。中心粒是研究的挑战，因为它们包含重复的DNA序列和很少的基因。该项目的目的是对中心粒中的序列与其功能相关，以及中心粒大小的变化或关键的丝粒结合蛋白（CENH3）的变化如何改变cencer粒的行为。 特别是该项目将研究遗传杂交和突变体，这些突变体可以诱导杂种中的丝粒衰竭和染色体丧失。丝粒修饰引起的染色体损失会导致单倍体植物，这对玉米育种者具有巨大价值，因为它们可以迅速加速新的近交系列的生产。预计所产生的信息和技术将直接应用于农业，不仅在玉米中，而且在所有利用单倍体作为繁殖工具的其他农作物中。关于培训和外展，该项目将为本科生和研究生以及植物基因组学和生物技术的博士后研究员提供研究培训。 此外，将举办一系列培训研讨会，以传播该项目中生成的技术和材料。所有项目成果将通过专门的项目网站以及包括NCBI，MaizeGDB和Gramene在内的长期存储库传播给研究社区。该项目的总体目标是了解玉米中心滴体的遗传和表观遗传成分，并揭示中心粒大小在单胎染色体消除中的作用，从而导致单倍体形成。特定目标是：1）确定使用新型染色体涂漆探针，染色体可视化工具，可以显着提高检测染色体结构变化的能力； 2）确定使用转移到燕麦中的玉米染色体以及经历了失活和重新活化循环的B染色体的染色质标记的套件如何受到丝粒大小和位置的变化的影响； 3）测试中心粒大小的差异是否会通过用隔离粒子筛选线的大小通过操纵基因组大小来修饰的丝粒，以及使用具有专门转基因的CENH3突变体来改变其尺寸的单亲基因组； 4）确定玉米在单亲基因组消除的情况下如何表现出cent虫的行为，尤其是在小麦X玉米和燕麦X玉米杂交中，这些杂交经常用于单倍体育种方案。