Studies of Spt6, a conserved and essential transcription and chromatin factor

Spt6（一种保守且必需的转录和染色质因子）的研究

• 批准号: 7632288
• 负责人: Cindy Fung
• 金额: $ 1.38万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7632288
• 关键词: Binding; Biochemical; Caenorhabditis elegans; Cell physiology; Chromatin; Chromatin Structure; Chromosome Structures; Cytomegalovirus; DNA; Data; Defect; Development; Elongation Factor; Eukaryota; Gene Expression; Genes; Genetic Transcription; Genome; Genomics; Goals; HIV-1; Heart Diseases; Histone Code; Histones; Immunocompromised Host; Inflammation; Location; Malignant Neoplasms; Maps; Metabolic; Molecular; Molecular Profiling; Mutation; Newborn Infant; Nucleosomes; Open Reading Frames; Process; Proteins; Regulation; Research; Role; Structure; Transcription Elongation; Viral Genes; Zebrafish; genome-wide; histone modification; human disease; in vivo; insight; novel; research study

DESCRIPTION (provided by applicant): Chromatin structure provides a necessary compaction to the eukaryotic genome, yet it also impairs protein access to DNA, thus imposing additional regulation on protein-DNA transactions. The overall objective of this project is to understand how chromatin controls gene expression. This application focuses on an essential and conserved transcription elongation factor, Spt6, which has critical and widespread roles in transcription elongation: Mutations in Spt6 has been shown to cause developmental defects in higher eukaryotes including C. elegans and zebrafish. In addition, Spt6 has been shown to regulate transcription of HIV-1 viral genes and genes of the human cytomegalovirus which infects immunosuppressed patients and newborns. Taken together, these findings highlight the importance of Spt6 in regulating chromatin structure and transcription during development and in human diseases, yet the molecular mechanism by which Spt6 functions is largely unknown. This study proposes biochemical and genomic approaches to understand how Spt6 regulates transcription. The TAP-tag purification of Spt6 in Aim 1 will comprehensively identify Spt6-interacting proteins in vivo. The focus will be on the interaction between Spt6 and histones and how the histone code regulates transcription elongation. The biochemical experiments proposed in Aim 2 will elucidate how Spt6 interacts with nucleosomes to alter chromosomal structure during transcription elongation and restore proper structure after transcription. The main focus will be on the role of Spt6 in transcription-dependent histone exchange. Finally the genome-wide ChlP-chip study proposed in Aim 3 will identify the binding locations of Spt6, and correlate them with existing genomic data such as transcription activity in known ORFs, spt6 expression profile, and histone modifications maps. The goal is to define all the cellular processes regulated by Spt6, and focus on novel targets of Spt6. The proposed studies will provide further insights into the role of Spt6 in DNA metabolic activities regulated by chromatin structure. Relevance: Disturbances in the process of transferring information from genes to proteins, known as transcription, are involved in many human diseases such as cancer, heart disease, and inflammation. The goal of this research is to elucidate the function of Spt6, an essential and evolutionarily conserved protein that has critical and widespread roles in transcription.

描述（由申请人提供）：染色质结构为真核生物基因组提供了必要的压实，但它也损害了蛋白质与DNA的接触，从而对蛋白质-DNA交易施加了额外的调节。该项目的总体目标是了解染色质如何控制基因表达。该应用集中于一个重要的和保守的转录延伸因子Spt6，它在转录延伸中具有关键和广泛的作用：Spt6的突变已被证明会导致包括秀丽隐杆线虫和斑马鱼在内的高等真核生物的发育缺陷。此外，Spt6已被证明可以调节HIV-1病毒基因和感染免疫抑制患者和新生儿的人巨细胞病毒基因的转录。综上所述，这些发现强调了Spt6在发育过程和人类疾病中调节染色质结构和转录的重要性，但Spt6功能的分子机制在很大程度上是未知的。本研究提出了生化和基因组方法来了解Spt6如何调节转录。在Aim 1中纯化Spt6的tap标签将全面鉴定体内与Spt6相互作用的蛋白。重点将放在Spt6和组蛋白之间的相互作用以及组蛋白代码如何调节转录伸长。Aim 2中提出的生化实验将阐明Spt6如何与核小体相互作用，在转录延伸过程中改变染色体结构，并在转录后恢复正常结构。重点将放在Spt6在转录依赖性组蛋白交换中的作用。最后，Aim 3中提出的全基因组cdna芯片研究将确定Spt6的结合位置，并将其与已知orf中的转录活性、Spt6表达谱和组蛋白修饰图谱等现有基因组数据相关联。目的是明确Spt6调控的所有细胞过程，并关注Spt6的新靶点。这些研究将进一步揭示Spt6在染色质结构调控的DNA代谢活动中的作用。相关性：在将信息从基因转移到蛋白质的过程中发生的干扰，即转录，与许多人类疾病有关，如癌症、心脏病和炎症。本研究的目的是阐明Spt6的功能，Spt6是一种重要的进化保守蛋白，在转录中具有关键和广泛的作用。