The Role of DEAD-box Proteins in Gene Expression

DEAD-box 蛋白在基因表达中的作用

• 批准号: 8827802
• 负责人: Elizabeth J Tran
• 金额: $ 28.08万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8827802
• 关键词: ATP phosphohydrolase; Acquired Immunodeficiency Syndrome; Binding; Binding Sites; Biochemical; Biochemical Pathway; Biogenesis; Biological Assay; Biological Models; Biology; Biomedical Research; Boxing; Cells; Code; Communities; Complex; Coupled; Enzymes; Epigenetic Process; Eukaryota; Family; Gene Expression; Gene Expression Profile; Gene Expression Regulation; Gene Proteins; Genes; Genetic; Genetic Transcription; Health; Human; In Vitro; Individual; Knowledge; Laboratories; Life; Link; Malignant Neoplasms; Mammalian Cell; Maps; Mediating; Medical; Messenger RNA; Modeling; Molecular; Molecular Chaperones; Molecular Genetics; Normal Cell; Nuclear; Oncogenes; Organism; Orthologous Gene; Physiological; Play; Process; Protein Family; Proteins; RNA; RNA Binding; RNA Decay; RNA Helicase; RNA Polymerase II; RNA Processing; RNA chemical synthesis; Regulation; Repression; Resistance; Role; Saccharomyces; Saccharomyces cerevisiae; Saccharomycetales; Series; Site; Transcript; United States National Institutes of Health; Untranslated RNA; Work; Yeasts; base; biological research; cancer type; cell growth; chromatin remodeling; driving force; epigenetic regulation; gene repression; genetic approach; genome-wide; helicase; human disease; in vitro Assay; in vitro activity; in vivo; insight; member; nervous system disorder; novel; overexpression; protein complex; protein protein interaction; transcription factor; tumor; tumorigenesis

DESCRIPTION (provided by applicant): Gene expression in eukaryotes is one of the most complex, highly orchestrated processes in living organisms. Numerous studies have shown that steps such as transcription, messenger RNA (mRNA) processing and mRNA decay, are highly coupled, forming an intricate molecular circuit for regulation of protein-coding genes. Central to this process, are a class of RNA helicases called DEAD-box proteins that perform essential roles in all aspects of RNA biology. Dbp2 is a largely uncharacterized member of the DEAD-box RNA helicase family in the budding yeast Saccharomyces cerevisiae. Whereas numerous studies have shown that the human (h) ortholog of Dbp2, hDDX5 or p68, functions as a transcriptional regulator, no transcriptional role has been described for Dbp2 and the precise molecular function of hDDX5 in this process is not understood. Our studies now provide the first demonstration that Dbp2 is required for nuclear gene expression steps in budding yeast, functioning at the interface between mRNA biogenesis and chromatin remodeling. Furthermore, our work demonstrates that Dbp2 functions at sites of non-protein coding RNA synthesis by RNA polymerase II. Herein, we propose to obtain a detailed understanding of Dbp2 using a combination of biochemical, molecular and genetic approaches. In Aim I, we will utilize a series of in vitro assays to biochemically characterize Dbp2 and subsequently analyze the enzymatic requirements for normal cell growth and gene expression. In Aim II, we will determine how Dbp2 functions in gene expression through a combination of molecular and genetic approaches. In Aim III, we will define and characterize the in vivo molecular interactions that enable Dbp2 to 'sense' nascent transcripts. Our long term working model is that Dbp2 is an enzymatic 'toggle' in the gene expression circuit that regulates the transcriptome. Thus, these studies have the potential to reveal novel mechanisms for genome-wide epigenetic regulation, an NIH strategic initiative reflective of the current challenges facing biomedical research. Importantly, numerous DEAD-box protein genes have been linked to human disease states including cancer, neurological disorders and AIDS. Therefore, uncovering the physiological role of individual DEAD-box proteins is a major challenge to basic biological research and the medical community.

描述（由申请人提供）：真核生物中的基因表达是活生物体中最复杂、高度协调的过程之一。许多研究表明，转录、信使RNA（mRNA）加工和mRNA降解等步骤是高度耦合的，形成了一个复杂的分子回路，用于调节蛋白质编码基因。这一过程的核心是一类称为DEAD-box蛋白的RNA解旋酶，它们在RNA生物学的各个方面都发挥着重要作用。Dbp 2是芽殖酵母酿酒酵母中DEAD盒RNA解旋酶家族的一个基本上未被表征的成员。尽管许多研究已经表明Dbp 2的人（h）直系同源物hDDX 5或p68作为转录调节因子起作用，但尚未描述Dbp 2的转录作用，并且hDDX 5在该过程中的精确分子功能尚不清楚。我们的研究现在首次证明Dbp 2是芽殖酵母中核基因表达步骤所必需的，在mRNA生物发生和染色质重塑之间的界面起作用。此外，我们的工作表明，Dbp 2的功能在网站的非蛋白质编码RNA合成的RNA聚合酶II。在此，我们建议使用生物化学，分子和遗传学方法的组合来获得Dbp 2的详细了解。在目的I中，我们将利用一系列体外测定来生物化学表征Dbp 2，随后分析正常细胞生长和基因表达的酶要求。在目的II中，我们将通过分子和遗传方法的组合来确定Dbp 2在基因表达中的功能。在目标III中，我们将定义和表征体内分子相互作用，使Dbp 2的“感”新生的成绩单。我们的长期工作模型是Dbp 2是基因表达回路中调节转录组的酶促“开关”。因此，这些研究有可能揭示全基因组表观遗传调控的新机制，这是NIH的一项战略举措，反映了生物医学研究目前面临的挑战。重要的是，许多死亡盒蛋白基因与人类疾病状态有关，包括癌症，神经系统疾病和艾滋病。因此，揭示个体DEAD盒蛋白的生理作用是基础生物学研究和医学界面临的重大挑战。