Investigating Paramutation at the Maize b1 Gene: Molecular Mechanisms of Heritable Epigenetic Gene Regulation

研究玉米 b1 基因的副突变：可遗传表观遗传基因调控的分子机制

• 批准号: 0950128
• 负责人: Vicki Chandler
• 金额: $ 66.77万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-15 至 2013-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0950128&HistoricalAwards=false
• 关键词: Investigating; Paramutation; Maize; b1; Gene

Intellectual Merit:How an individual's genes are activated or silenced is an essential question impacting all fields of biology. Gene expression patterns, i.e. which genes are on and which are off in different tissues and during development, are highly reproducible among individuals of each species and those patterns are efficiently reset every generation. One exception to these genetic rules is paramutation in maize. Paramutation leads to certain genes becoming silenced and that silencing is retained when the genes are transmitted to offspring. Depending on which genes are silenced dramatic changes in the plant's growth and development can be observed. Prior work has demonstrated that these heritable changes in gene expression are mediated by RNA, demonstrating RNA is not just a vehicle for DNA's commands; it is able to issue its own commands that alter how genes are expressed in the next generation. This project is to characterize a gene that is required for paramutation, mop3 (mediator of paramutation3). Initial research has demonstrated that mop3 acts at a distinct step in RNA mediated gene silencing relative to other previously characterized genes required for paramutation. Thus, new mechanistic insights should be gained from further study of mop3 as well as from the isolation and characterization of additional genes required for paramutation, another major goal of this project. Understanding mechanisms for heritable changes in gene expression will provide new insights into how plants might mediate adaptive responses to a changing environment. Broader Impacts: The investigators for this project have had a long standing commitment to training and outreach. During the past 12 years, 5 postdoctoral fellows, 8 graduate students, 45 undergraduate students, 10 high school students and 5 high school teachers have participated in the research efforts that generated the data that formed the basis for this project. The current research project will provide training for two undergraduate students each year and a high school teacher and her students. The high school teacher will participate in a summer internship each year that will involve direct participation in the experiments and designing curriculum to engage the high school students during the academic year. The teacher will participate in a broad network with other teachers so that each person's curriculum innovation can be shared and thus, contribute to an increase in the science literacy of a larger number of students.

智力优势：一个人的基因是如何被激活或沉默的是一个重要的问题，影响着生物学的所有领域。基因表达模式，即在不同的组织和发育过程中哪些基因是开启的，哪些基因是关闭的，在每个物种的个体之间是高度可重复的，并且这些模式在每一代都被有效地重置。这些遗传规律的一个例外是玉米的副突变。顺突变导致某些基因沉默，当基因传递给后代时，沉默会保留下来。根据哪些基因被沉默，可以观察到植物生长和发育的巨大变化。先前的工作已经证明，这些基因表达的遗传变化是由RNA介导的，这表明RNA不仅仅是DNA命令的载体;它能够发出自己的命令，改变基因在下一代中的表达方式。本项目是为了表征一个基因，这是所需的副突变，mop 3（mediator of paramutation 3）。初步研究表明，相对于其他先前表征的副突变所需的基因，mop 3在RNA介导的基因沉默中的不同步骤起作用。因此，新的机制的见解，应获得进一步研究的mop 3以及从分离和表征所需的副突变，该项目的另一个主要目标的额外的基因。了解基因表达的遗传变化机制将为植物如何调节对变化环境的适应性反应提供新的见解。更广泛的影响：该项目的调查人员长期致力于培训和推广。在过去的12年中，5名博士后研究员，8名研究生，45名本科生，10名高中生和5名高中教师参加了研究工作，产生了构成该项目基础的数据。目前的研究项目将每年为两名本科生和一名高中教师及其学生提供培训。 高中教师将参加每年的暑期实习，这将涉及直接参与实验和设计课程，使高中学生在学年期间参与。教师将与其他教师一起参与广泛的网络，以便每个人的课程创新可以共享，从而有助于增加更多学生的科学素养。