GEPR: Epigenetic Regulation of Mutator Transposons in Maize

DNA序列是信息代代相传的主要手段。然而，信息也可以作为DNA和蛋白质(如与DNA相关的组蛋白)的化学修饰来传播。与初级DNA序列变化无关的可遗传变异称为表观遗传变异。表观遗传变异之所以特别耐人寻味，是因为它涉及的变化既可以遗传，也可以逆转。关于这些变化如何以及为什么发生的规则，人们仍然知之甚少。转座子，或“跳跃基因”，表现出非常容易识别的表观遗传变异，使它们成为理解其原因和后果的理想模型。在转座子中，玉米中的突变元件已被证明特别有用。利用一系列遗传资源，特别是携带单一活性突变转座子的玉米品系，已经有可能诱导和繁殖各种不同的表观遗传状态。这个项目的目标是确定与这些状态中的每一个状态相关的分子。将特别强调表观遗传状态随时间变化的方式，无论是在单个植物的发育过程中，还是在多个世代的过程中。这些数据旨在通过在明确定义的模型系统的背景下提供对这些修饰的特定模式的功能评估，来补充对DNA和组蛋白修饰的全球分析。更广泛的影响：对表观遗传信息被保留、存储、继承和改变的手段的复杂理解，对发展、生态学、人类疾病和进化论等多个领域都有影响。此外，由于突变因子系统是玉米基因突变的主要途径，因此调节突变因子活性的能力将使整个玉米群体受益。与使用Mu杀菌剂有关的材料和信息将通过网站(http://tinyurl.com/6xftvh和http://tinyurl.com/59fdwo)，、玉米通讯和玉米合作库存中心)免费提供。该项目将受益于SEED项目的参与，该项目旨在让历史上代表性不足的高中生接触到研究环境。通过与伯克利高中的合作，该项目还将在每年夏天接待两名实习生。每个学生将在一个具体问题上与主要研究人员密切合作，每个学生将在每个实地考察季节结束时提交他们的工作结果。

DNA sequence is the primary means by which information is propagated from generation to generation. However, information can also be propagated as chemical modifications of both DNA and proteins, such as histones, that are associated with DNA. Heritable variation not associated with changes in the primary DNA sequence is called epigenetic variation. What makes epigenetic variation particularly intriguing is that it involves changes that can be both heritable and reversible. The rules governing how and why those changes occur remain poorly understood. Transposons, or "jumping genes", exhibit an extraordinary degree of easily identifiable epigenetic variation, making them ideal models for understanding its causes and consequences. Among transposons, Mutator elements in maize have proved to be particularly useful. Using a series of genetic resources, particularly a maize line that carries a single active Mutator transposon, it has been possible to induce and propagate a wide variety of distinct epigenetic states. The goal of this project is to determine the molecular correlates to each of these states. Particular emphasis will be placed on the ways in which epigenetic states can change over time, either over the course of the development of an individual plant, or over the course of multiple generations. These data are meant to complement global analysis of DNA and histone modification by providing functional assessments of particular patterns of these modifications in the context of a well-defined model system. Broader Impacts: A sophisticated understanding of the means by which epigenetic information is retained, stored, inherited and altered has implications for fields as diverse as development, ecology, human disease and evolutionary theory. In addition, because the Mutator system is a primary means by which genes are mutated in maize, an ability to modulate Mutator activity will benefit the entire maize community. Material and information having to do with the use of Mu killer will be made freely available via web sites (http://tinyurl.com/6xftvh and http://tinyurl.com/59fdwo), the Maize Newsletter and the Maize Cooperation Stock Center. The project will benefit from participation in project SEED, a program designed to expose historically under-represented high school students to research environments. Through a collaboration with Berkeley High School, the project will also host two students as interns each summer. Each student will work in close collaboration with the primary investigator on a specific problem, and each will present the results of their work at the end of each field season.