DNA damage response and DDB

DNA损伤反应和DDB

基本信息

批准号：
7228937
负责人：
Pradip Raychaudhuri
金额：
$ 28.62万
依托单位：
UNIVERSITY OF ILLINOIS AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-05-15 至 2010-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7228937
关键词：
1-Phosphatidylinositol 3-Kinase 7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide Adult Aging Alkylating Agents Alleles Ataxia-Telangiectasia-Mutated protein kinase Binding CDT1 Gene Cell Aging Cell Cycle Cell Cycle Progression Cell Line Cells Checkpoint kinase 1 Chromatin Cisplatin Complex Cyclophosphamide DDB Chlorinated Hydrocarbons DNA DNA Damage DNA Repair DNA Replication Factor DNA biosynthesis DNA lesion DNA-Binding Proteins Decompression Sickness Disease E1A-associated p300 protein EP300 gene Embryo Exhibits Fibroblasts Fission Yeast Genes Genetic Genetic Transcription Hand Incidence JUN gene Knock-out Link Malignant Neoplasms Mediating Methyl Methanesulfonate Mouse Strains Mus Mutation Numbers Pathway interactions Peptide Initiation Factors Phase Phosphoinositide-3-Kinase, Catalytic, Gamma Polypeptide Phosphotransferases Physiological Play Principal Investigator Process Proteolysis Proto-Oncogene Proteins c-jun Range Recruitment Activity Replication Initiation Reporting Role Signal Pathway Signal Transduction Somatic Cell Specificity Stress System TP53 gene Testing Time Tissues Tobacco Ubiquitin Ubiquitination Xenopus oocyte Yeasts age related aplidine base chromatin remodeling complement deficiency cullin 4A genetic regulatory protein in vivo insight multicatalytic endopeptidase complex programs recombinase repaired response senescence sensor temperature sensitive mutant tissue regeneration tumor ubiquitin-protein ligase ultraviolet damage ultraviolet irradiation

项目摘要

DESCRIPTION (provided by applicant): DNA damage in somatic cells is one of the main causes of aging and many age-related diseases, including cancer and decreased tissue regeneration. Cells respond to DNA damage by triggering the checkpoint pathways that delay the cell cycle progression allowing time for DNA repair. The checkpoint pathway involves association of the PI3 kinases ATM/ATR with damaged chromatin and subsequent activation of the checkpoint kinases (Chk1 and Chk2) and p53, as well as other regulatory proteins that control the fate of a cell following DNA damage. Despite significant advances on the damage-response pathways, the mechanisms (sensors) that recruit ATM/ATR to damaged-DNA are not known. Our recent studies revealed that the damaged-DNA binding protein DDB functions as a damage-sensor that recruits ATR to the UV-damaged chromatin to activate the ATR-Chk1/p53 pathway. The objectives of this proposal are to further investigate the damage-sensor function of DDB and determine the spectrum of DNA damage for which DDB functions as a sensor leading to the activation of the ATR-checkpoint pathway. DDB is composed to two subunits: DDB1 and DDB2. The DDB2 subunit is transcriptionally induced by p53 upon DNA damage. We will test the hypothesis that the p53-induced expression of DDB2 is critical for a sustained activation of the checkpoints following DNA damage. Also, we plan to develop a knockout strain of mice lacking DDB1 to investigate the functions of DDB1 in a physiological context. Accumulating evidence indicates that the DDB1 subunit possesses functions that are independent of the DDB2 subunit. For example, DDB1 has been shown to be involved in the proteolysis of c-jun in conjunction with cullin 4A. Also, the fission yeast ortholgue of DDB1 has been implicated in the proteolysis through the ubiquitin-proteasome pathway. A conditional knockout strain of mice will be important in evaluating the various functions of DDB1 in a physiological context. The specific aims are: 1. Does DDB function as a sensor for a wide range of DNA damages? Is the DDB-mediated activation of ATR-Chk1 linked to initiation of DNA replication? Does the DDB-mediated activation of ATR-Chk1 involve chromatin-remodeling by CBP/p300? 2.Does DDB play a role in the sustained activation of checkpoints following DNA damage? Does DNA damage-induced senescence depend upon DDB? 3. What are the in vivo functions of DDB1?

描述（由申请人提供）：体细胞中的 DNA 损伤是衰老和许多与年龄相关的疾病的主要原因之一，包括癌症和组织再生能力下降。细胞通过触发检查点途径来响应 DNA 损伤，从而延迟细胞周期进程，为 DNA 修复留出时间。检查点通路涉及 PI3 激酶 ATM/ATR 与受损染色质的关联，以及随后激活检查点激酶（Chk1 和 Chk2）和 p53，以及在 DNA 损伤后控制细胞命运的其他调节蛋白。尽管损伤响应途径取得了重大进展，但将 ATM/ATR 募集到受损 DNA 的机制（传感器）尚不清楚。我们最近的研究表明，受损的 DNA 结合蛋白 DDB 作为损伤传感器发挥作用，将 ATR 招募到紫外线损伤的染色质上，以激活 ATR-Chk1/p53 通路。本提案的目的是进一步研究 DDB 的损伤传感器功能，并确定 DDB 作为传感器导致 ATR 检查点通路激活的 DNA 损伤谱。 DDB由两个子单元组成：DDB1和DDB2。 DDB2 亚基在 DNA 损伤后由 p53 转录诱导。我们将检验以下假设：p53 诱导的 DDB2 表达对于 DNA 损伤后检查点的持续激活至关重要。此外，我们计划开发一种缺乏 DDB1 的小鼠敲除品系，以研究 DDB1 在生理环境中的功能。越来越多的证据表明，DDB1 亚基具有独立于 DDB2 亚基的功能。例如，DDB1 已被证明与 cullin 4A 一起参与 c-jun 的蛋白水解。此外，DDB1 的裂殖酵母直系同源物通过泛素-蛋白酶体途径参与蛋白水解。条件性敲除小鼠品系对于评估 DDB1 在生理环境中的各种功能非常重要。具体目标是： 1. DDB 是否可以作为多种 DNA 损伤的传感器？ DDB 介导的 ATR-Chk1 激活是否与 DNA 复制的启动有关？ DDB 介导的 ATR-Chk1 激活是否涉及 CBP/p300 的染色质重塑？ 2.DDB是否在DNA损伤后检查点的持续激活中发挥作用？ DNA 损伤诱导的衰老是否依赖于 DDB？ 3. DDB1在体内有哪些功能？