Functions of SRAP domain proteins in DNA metabolism

SRAP结构域蛋白在DNA代谢中的功能

基本信息

批准号：
9901531
负责人：
David K Cortez
金额：
$ 44.95万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9901531
关键词：
Aging Agrochemicals Air Pollution Alkylating Agents Alkylation Bacteria Binding Biochemical Biochemical Genetics Bypass Carbon Cells Chemicals Chloroform Clinical Coupled Cysteine Cytosine DNA DNA Binding DNA Damage DNA Repair DNA Repair Gene DNA Repair Pathway DNA biosynthesis DNA lesion DNA metabolism DNA replication fork DNA-Directed DNA Polymerase DNA-protein crosslink Data Detergents Diet Disease Environmental Exposure Enzymatic Biochemistry Epigenetic Process Exposure to Failure Food Frequencies Future Gene Expression Genes Genetic Genetic Screening Genetic Structures Genome Genome Stability Genotoxic Stress Guanine Human Hydroxyl Radical Hypersensitivity Ionizing radiation Knock-out Lesion Life Ligands Link Maintenance Malignant Neoplasms Methods Modeling Mutagenesis Mutagens Mutation N-terminal Nitrosamines Organism Oxidants Oxidative Stress Oxides Pathway interactions Peptide Hydrolases Phenotype Plastics Polymerase Process Proteins Proteomics Radiation Reporting Resolution S Phase SOS Response SS DNA BP Saccharomyces cerevisiae Single-Stranded DNA Site Solvents Source Structure System Tertiary Protein Structure Testing Therapeutic Intervention Toxic Environmental Substances UV Radiation Exposure Yeasts adduct base blastomere structure crosslink endonuclease environmental toxicology experimental study fitness genetic approach genome integrity innovation loss of function nuclease oxidation potassium bromate prevent protein crosslink protein function recruit repair enzyme repaired response suicide enzyme targeted treatment

项目摘要

PROJECT SUMMARY Thousands of abasic sites form daily in each of our cells. Many types of environmental toxins that cause alkylation or oxidation of DNA bases to form N7-guanine adducts and 8-oxoguanine induce abasic sites. For example, N-nitrosamines that are found in foods, detergents, solvents, plastics, and agricultural chemicals as well as chemicals like carbon tetracholoride, potassium bromate, and chloroform that induce oxidative stress all increase the frequency of abasic sites in DNA. Failures in managing this ubiquitous form of DNA damage can cause a variety of diseases including cancer. The known mechanisms of repair require an intact DNA duplex; however, abasic sites form more readily in single-stranded DNA where they are impediments to replicative polymerases. We utilized unbiased proteomic and genetic approaches to understand how replication forks deal with challenges to genotoxic stresses with the premise that uncharacterized proteins identified in both approaches would be strong candidates for new DNA damage response proteins. Both the proteomic and genetic screens identified HMCES (hydroxyl-methyl cytosine embryonic cell specific) as a candidate genome maintenance protein functioning at replication forks. HMCES was reported to bind and remove 5-hydroxymethyl cytosine from DNA and thereby regulate gene expression. Our preliminary data suggests that HMCES independently functions as a replication- associated DNA repair protein. HMCES contains an evolutionarily ancient domain (SRAP). We hypothesize that SRAP proteins provide a mechanism to repair or tolerate DNA damage during DNA replication. This proposal will utilize biochemical, genetic, and structural approaches in human, yeast, and bacterial systems to determine how SRAP proteins maintain genome stability. Completing these studies will generate paradigm setting discoveries within the fields of environmental toxicology, DNA repair, DNA replication, epigenetic control, and enzymology.

项目摘要每天在我们的每个细胞中每天形成成千上万个无碱性位点。导致许多类型的环境毒素 DNA碱基的烷基化或氧化形成N7-瓜氨酸加合物和8-氧气的诱导无碱性位点。例如，在食品，清洁剂，溶剂，塑料和农业中发现的N-亚硝胺化学物质以及诱导的化学物质，例如四氯乙酸酯，溴酸钾和氯仿氧化应激均增加了DNA中无碱性位点的频率。管理这种无处不在的失败 DNA损伤的形式会导致包括癌症在内的各种疾病。已知的修复机制需要完整的DNA双链体；但是，在单链的DNA中更容易形成无碱性位点是复制聚合酶的障碍。我们利用公正的蛋白质组学和遗传学方法了解复制叉如何应对遗传毒性压力的挑战，前提是两种方法中鉴定出的未表征的蛋白质都将是新的DNA损伤的强大候选者反应蛋白。蛋白质组学和遗传筛选都鉴定出HMCE（羟基胞嘧啶胚胎细胞特异性）作为候选基因组维持蛋白在复制叉时的功能。据报道，HMCE结合并从DNA中去除5-羟基甲基胞嘧啶，从而调节基因表达。我们的初步数据表明，HMCES独立起作用作为复制 - 相关的DNA修复蛋白。 HMCE包含一个进化上古老的领域（SRAP）。我们假设SRAP蛋白提供了在DNA期间修复或耐受DNA损伤的机制复制。该建议将利用人类，酵母和细菌系统确定SRAP蛋白如何保持基因组稳定性。完成这些研究将在环境毒理学，DNA修复，DNA领域内产生范式设置发现复制，表观控制和酶学。