Structural Studies of the Eukaryotic Transcription Initiation Machinery

真核转录起始机制的结构研究

基本信息

批准号：
9131755
负责人：
Eva Nogales
金额：
$ 24.95万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-05-01 至 2018-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9131755
关键词：
Active Sites Architecture Binding Biochemical Biochemistry Cells Clinic Clinical Complex Cues DNA DNA Structure Development Developmental Process Disease Electron Microscopy Essential Genes Gene Activation Gene Expression Gene Expression Regulation Genes Genetic Transcription Growth Health Human Image Analysis Imagery Indium Individual Light Malignant Neoplasms Mediating Messenger RNA Modeling Molecular Molecular Genetics Molecular Profiling Neoplasm Metastasis Neoplasms Nucleotides Organism Peptide Initiation Factors Pluripotent Stem Cells Positioning Attribute Process Property Proteins Regulation Regulator Genes Research Rest Source Stem Cell Research Structure System Techniques Transcription Coactivator Transcription Elongation Transcription Factor TFIIA Transcription Factor TFIIB Transcription Initiation Transcription Initiation Site Transcription Process Transcriptional Regulation angiogenesis base cell growth cofactor environmental change flexibility functional plasticity gene repression helicase in vivo induced pluripotent stem cell melting microscopic imaging novel particle polypeptide promoter protein complex protein structure reconstitution reconstruction response transcription factor TFIIH zygote

项目摘要

Transcriptional regulation of gene expression is a complex task, critical for growth and survival, whether as part of the developmental process from the fertilized egg, or when adapting to changing environmental conditions. The transcription initiation step is arguably the most regulated step in gene transcription, as fine tuning both its rate and synchrony can serve as a key control point to produce organism-wide changes in gene expression profiles in response to developmental and environmental cues. Not surprisingly, the complexity of gene regulatory circuitries is paralleled by the size and complexity of the molecular players involved in transcription initiation. Over the past 30 years, biochemistry, molecular genetics, and in vivo studies have uncovered most, if not all, of the central components of the transcriptional apparatus. However, a mechanistic understanding of gene expression in humans poses a formidable challenge and lags dramatically behind. A major obstacle is that the transcriptional machinery comprises more than 100 individual polypeptides that operate as a huge and dynamic assemblage made up of functionally distinct multi-subunit complexes, many of them only accessible from endogenous sources. We are using single particle EM reconstruction to characterize the architecture, dynamics and interactions of large human complexes essential for gene regulation. 3D Cryo-EM reconstruction is a technique ideally suited to this task, as it requires limited amounts of material, is optimal to study very large assemblies, and is has the potential to detect and characterize conformational flexibility, a property to may prove critical to be able to describe the functional plasticity required in transcriptional complexes like TFIID, an essential hub in this process that needs to bind to different DNA core promoters and integrate the input from a large variety of transcriptional activators and cofactors. The significance to human health of a fundamental understanding of how gene transcription is switched on and off cannot be overstated. Such significance is highlighted by the fact that development of various cancers is accompanied by alterations in gene expression leading to various aspects of the disease, and by the discovery of induced pluripotent stem cells, where the expression of 3-4 global transcriptional activators is sufficient to introduce gene expression changes needed to transition into a pluripotent state. By understanding the protein structures necessary for gene activation, we will guide future research into the development of novel treatments that target the control of gene expression mediating cell growth, neoplasia, metastasis, and angiogenesis in humans or those aimed at facilitating the transition of induced pluripotent stem cells research into the clinic.

基因表达的转录调节是一项复杂的任务，对生长至关重要和生存，无论是作为受精卵发育过程的一部分，还是适应不断变化的环境条件时。转录启动步骤是可以说是基因转录中最受调节的步骤，因为它的速率和同步可以作为产生范围有机体变化基因变化的关键控制点响应发展和环境线索的表达谱。毫不奇怪，基因调节电路的复杂性与大小相似和参与转录启动的分子参与者的复杂性。过去 30年，生物化学，分子遗传学和体内研究大多数（如果并非全部是转录设备的中心组成部分。但是，对人类基因表达的机械理解带来了巨大的挑战并落后于落后。主要障碍是转录机械由100多种单独的多肽组成，这些多肽是一个巨大而动态的由功能上不同的多生成络合物组成的组合，其中许多仅可从内源性来源访问。我们正在使用单个粒子EM重建表征大型人类综合体的结构，动态和相互作用对于基因调节必不可少的。 3D Cryo-Em重建是一种理想的技术这项任务，因为它需要有限的材料，因此非常适合学习很大组件，并且具有检测和表征构象柔韧性的潜力，能够描述所需的功能可塑性可能是至关重要的转录复合物（如TFIID），这是此过程中的基本集线器，需要结合到不同的DNA核心启动子，并整合了各种各样的输入转录激活剂和辅因子。对人类健康的意义，对基因的基本了解转录打开和关闭不能被夸大。这种意义是通过以下事实强调了各种癌症的发展基因表达的改变导致疾病的各个方面，并由发现诱导多能干细胞的发现，其中3-4全局的表达转录激活剂足以引入所需的基因表达变化过渡到多能状态。通过了解所需的蛋白质结构基因激活，我们将指导未来研究新疗法的发展靶向介导细胞生长，肿瘤，转移的基因表达的控制和人类或旨在促进诱导过渡的人的血管生成多能干细胞研究诊所。

项目成果

期刊论文数量（14）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Architecture of the human XPC DNA repair and stem cell coactivator complex.

人类 XPC DNA 修复和干细胞共激活剂复合物的结构。

DOI：
10.1073/pnas.1520104112
发表时间：
2015
期刊：
Proceedings of the National Academy of Sciences of the United States of America
影响因子：
11.1
作者：
Zhang,ElisaT;He,Yuan;Grob,Patricia;Fong,YickW;Nogales,Eva;Tjian,Robert
通讯作者：
Tjian,Robert

How Cryo-EM Became so Hot.