RNA Polymerase Transcription Past DNA Adducts

RNA 聚合酶转录 DNA 加合物

基本信息

批准号：
7470187
负责人：
David A Scicchitano
金额：
$ 0.61万
依托单位：
NEW YORK UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2000
资助国家：
美国
起止时间：
2000-09-30 至 2009-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7470187
关键词：
4-nitroimidazole Active Sites Address Adenine Adopted Affect Area Aromatic Polycyclic Hydrocarbons Base Composition Base Sequence Behavior Benzo(a)pyrene Biochemical Biological Biological Process Biology Bypass Carcinogens Cell Nucleus Cells Characteristics Chemicals Chemistry Chinese Hamster Ovary Cell Cockayne Syndrome Collaborations Complement Complex Computer Simulation Cytosol DNA DNA Adducts DNA Damage DNA Repair DNA Repair Pathway DNA Sequence DNA lesion DNA-Directed DNA Polymerase DNA-Directed RNA Polymerase Data Defect Development Disease Enzymes Epoxy Compounds Event Excision Exhibits Exposure to Frequencies Funding Future Gene Expression Genes Genetic Genetic Transcription Genome Genomics Glycol Goals Grant Growth Guanine Human Joints Kinetics Knowledge Learning Length Lesion Letters Light Literature Messenger RNA Metabolic Clearance Rate Methods Modeling Molecular Molecular Conformation Mutagenesis Mutation New York Nucleotide Excision Repair Nucleotides Oxidoreductase Pathway interactions Patients Pattern Pharmaceutical Preparations Phase Phenotype Play Polymerase Portraits Positioning Attribute Preparation Primer Extension Principal Investigator Property Protein Conformation Proteins Protocols documentation Publishing Purpose Pyrenes RNA RNA Conformation RNA Polymerase II RNA Sequences RNA chemical synthesis RNA primers Range Relative (related person)Reporting Research Research Personnel Ribonucleotides Role Series Shapes Signal Transduction Site Structural Models Structure Study models System T7 RNA polymerase Techniques Testing Title Transcript Transcription Elongation Transcription-Coupled Repair Tumorigenicity Universities Work adduct base benzo(c)phenanthrene benzo(g)chrysene clinical phenotype computer generated falls interest molecular dynamics molecular mechanics molecular modeling prevent professor promoter protein structure pyrene repaired research study size stereochemistry tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): The long range goal of this research is to gain a detailed understanding of how covalently modified bases in DNA affect RNA polymerase behavior during the elongation phase of transcription, with the ultimate objective of producing detailed structural models that portray RNA polymerase interactions at bulky and small adducts found in DNA. The following four Specific Aims will be targeted toward this: (1) to assess the effects of transcription past site-specific lesions on elongation past the damaged or modified site; (2) to determine the base sequence of full-length transcripts, and to characterize the base composition at the 3'- ends of truncated transcripts; (3) to determine Km, and Vrnax values for base addition at DNA adducts during transcription; and (4) to employ computer-modeling techniques to provide characteristics of transcription complexes stalled at DNA adducts. It is now quite clear that certain DNA lesions can cause RNA polymerase to stall at the modified site, resulting in a truncated transcript, or progress past the altered base, producing full-length RNA. Stalled transcription complexes signal transcription-coupled DNA repair. The importance of transcription-coupled DNA repair is evidenced by the clinical phenotype observed when it is aberrant, as is seen in patients with Cockayne's syndrome, a disease characterized by severe growth and developmental defects. There are broad and significant implications for preferential clearance of DNA damage from discrete, active genetic loci: Biases in mutagenesis can exist; correlations of DNA damage and repair with tumorigenesis might be stronger when preferential clearance rates for a particular adduct are used for making the comparisons, rather than total genomic repair; and the actual removal of adducts from the transcribed strand of an expressed gene might be very dependent on their ability to impede RNA synthesis.

描述（由申请人提供）：这项研究的远距离目标是详细了解DNA中的共价修改碱会影响转录延长阶段的RNA聚合酶行为，其最终目的是生成详细的结构模型，以描绘DNA中的笨重和小型累积的RNA聚合酶相互作用。以下四个特定目标将针对这一点：（1）评估转录过去特定现场病变对损坏或修改部位的伸长的影响；（2）确定全长转录本的基本序列，并在截短的转录本的3'-末端表征基本组成；（3）确定在转录过程中DNA加合物处的碱基添加的km和VRNAX值；（4）采用计算机建模技术来提供停滞在DNA加合物处的转录复合物的特征。现在很明显，某些DNA病变会导致RNA聚合酶在修饰的位点停滞，从而导致转录本截断，或者经过改变的碱基，从而产生全长RNA。停滞的转录复合物信号转录耦合的DNA修复。转录耦合DNA修复的重要性由异常时观察到的临床表型证明，如Cockayne综合征患者所见，这种疾病以严重的生长和发育缺陷为特征。对于从离散的，主动遗传基因座的DNA损伤的优先清除具有广泛而显着的意义：可以存在诱变中的偏见。当使用特定加合物的优先清除率来进行比较时，而不是总基因组修复时，DNA损伤和修复与肿瘤发生的相关性可能会更强。并且从表达基因的转录链中实际去除加合物可能非常取决于它们阻碍RNA合成的能力。