Developmental Functions of SNR1 and the BRM Chromatin Remodeling

SNR1 的发育功能和 BRM 染色质重塑

• 批准号: 1122001
• 负责人: Andrew Dingwall
• 金额: $ 72.03万
• 依托单位: Loyola University Stritch School of Medicine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-15 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1122001&HistoricalAwards=false
• 关键词: Developmental; Functions; SNR1; BRM; Chromatin

Intellectual Merit: The ability of a cell to access genetic information embedded in the genome is essential for proper development; thus, it is of great importance to understand the cellular processes that guide proper gene regulation in vivo. The nucleosome, composed of a set of core histone proteins and DNA, is the basic building block of chromatin and acts as a primary scaffold for chromosome protection and compaction. Nucleosomes also act as barriers to restrict access to DNA and as a result can serve to prevent the expression of genes and consequently block cell division. Chromatin remodeling is a key step in the process of gene activation through disruptions of DNA-histone contacts that result in changes in DNA wrapping within nucleosomes, referred to as chromatin accessibility. Highly conserved from yeast to vertebrates, chromatin remodeling complexes (such as the SWI/SNF complex) function as essential cofactors to initiate gene transcription and assist in the regulation of transcription elongation as well as alternative splicing that produces different forms of the same gene. Fundamental questions needing to be resolved include how these complexes are targeted to genes in vivo and how they contribute mechanistically to both transcription activation and repression. Although generally acknowledged that chromatin structure can influence how gene transcripts are spliced to produce a variety of protein forms from the same gene, many assumptions are made and questions remain concerning the role of the nucleosome in vivo. This project tests the hypothesis that chromatin remodeling complexes contribute to gene repression through regulated remodeling of nucleosomes that normally act as impediments to transcription elongation at critical points in development. The research will address the in vivo functions of nucleosome remodeling complexes using biochemical assays of chromatin compaction, protein binding to chromatin and unique leading edge genetic tools developed for this research study. This project uses the fruitfly Drosophila melanogaster as a genetic model system to provide much needed and more detailed knowledge of the mechanisms by which chromatin remodeling complexes participate in programming gene expression during development. The results derived from this research are likely to have important and widespread implications for understanding the roles of the chromosome building blocks in gene regulation, as well as the remodeling enzyme complexes that control how that genome information is accessed by other factors, including the regulation of RNA polymerase elongation and alternative splicing in diverse systems.Broader Impacts: The broader impacts of this project include (1) providing opportunities for high school, undergraduate and graduate (both MS and PhD) students to directly participate in mentored research, and (2) widespread dissemination of the results of this research through invited seminars and presentations at national meetings. Specifically, this research project will seek to actively recruit and train students from traditionally underrepresented minority groups, including local high school students from the Maywood (IL) and greater Chicago area, as well as college undergraduate students. Trainees will be mentored in basic research and assigned non-trivial roles on the project. Multidisciplinary training and education are vital to prepare students for diverse science careers; therefore, students are encouraged to think creatively and, in order to function effectively in the laboratory, they are taught developmental biology, genetics, scientific techniques, molecular/cellular biology and biochemistry. Students are also taught how to read and evaluate scientific literature, they are encouraged to identify role models to enforce their educational objectives, and to train them to give clear presentations, they attend and present at lab meetings for faculty and other students. Students are also encouraged to present their work at regional and national meetings and also to collaborate with expert investigators outside the institution in diverse scientific fields to enhance their multidisciplinary training experience. Within the institution, this work represents the only eukaryotic model system utilizing developmental genetics, and graduate lectures incorporate aspects of the work from the lab.

智力优势：细胞获取基因组中嵌入的遗传信息的能力对于正常发育至关重要;因此，了解指导体内正确基因调控的细胞过程非常重要。核小体由一组核心组蛋白和DNA组成，是染色质的基本组成部分，并作为染色体保护和压缩的主要支架。核小体也作为限制DNA进入的屏障，因此可以阻止基因的表达，从而阻止细胞分裂。染色质重塑是基因激活过程中的关键步骤，通过破坏DNA-组蛋白接触，导致核小体内DNA包裹的变化，称为染色质可及性。从酵母到脊椎动物高度保守，染色质重塑复合物（如SWI/SNF复合物）作为必需的辅因子起作用以启动基因转录并协助调节转录延伸以及产生相同基因的不同形式的选择性剪接。需要解决的基本问题包括这些复合物如何在体内靶向基因，以及它们如何在机制上促进转录激活和抑制。虽然普遍认为，染色质结构可以影响基因转录本如何拼接产生各种蛋白质形式从同一个基因，许多假设和问题仍然是关于核小体在体内的作用。该项目测试的假设，染色质重塑复合物有助于基因抑制，通过调节核小体，通常作为转录延长在发展的关键点的障碍重塑。该研究将使用染色质压实，蛋白质与染色质结合的生物化学测定以及为这项研究开发的独特前沿遗传工具来解决核小体重塑复合物的体内功能。该项目使用果蝇作为遗传模型系统，以提供更需要的和更详细的知识的机制，染色质重塑复合物参与编程基因表达在发展过程中。这项研究的结果可能对理解染色体构建模块在基因调控中的作用以及控制基因组信息如何被其他因素访问的重塑酶复合物（包括RNA聚合酶延伸和不同系统中的选择性剪接的调控）具有重要和广泛的影响。该项目的更广泛影响包括：（1）为高中生、本科生和研究生（硕士和博士）提供直接参与指导研究的机会;（2）通过应邀在国家会议上举办研讨会和演讲，广泛传播这项研究的成果。具体而言，该研究项目将寻求积极招募和培训传统上代表性不足的少数群体的学生，包括来自梅伍德（IL）和大芝加哥地区的当地高中生，以及大学本科生。学员将接受基础研究的指导，并在项目中担任重要角色。多学科的培训和教育是至关重要的，为学生准备不同的科学事业;因此，鼓励学生创造性地思考，为了在实验室有效地发挥作用，他们被教导发育生物学，遗传学，科学技术，分子/细胞生物学和生物化学。学生还被教导如何阅读和评估科学文献，鼓励他们确定榜样，以执行他们的教育目标，并训练他们给出清晰的演示文稿，他们出席并出席教师和其他学生的实验室会议。还鼓励学生在区域和国家会议上介绍他们的工作，并与机构外不同科学领域的专家调查人员合作，以加强他们的多学科培训经验。在该机构内，这项工作代表了唯一利用发育遗传学的真核模型系统，研究生讲座将实验室工作的各个方面结合起来。