Regulation of DNA Damage and Repair in Heterochromatin

异染色质 DNA 损伤和修复的调控

基本信息

批准号：
8728263
负责人：
Gary H KARPEN
金额：
$ 35.23万
依托单位：
UNIVERSITY OF CALIF-LAWRENC BERKELEY LAB
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-15 至 2017-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8728263
关键词：
Animals Behavior Biochemical Genetics Bioinformatics Biological Biological Models Cancer Diagnostics Cells Characteristics Chromatin Chromosomes Cultured Cells Cytoskeleton DNA DNA Damage DNA Repair DNA Sequence DNA Sequence Rearrangement Development Diagnosis Double Strand Break Repair Drosophila genus Ensure Environment Epigenetic Process Event Foundations Future Gene Proteins Genome Genome Stability Genomic Instability Genomics Goals Heterochromatin Human Human Genome Image Analysis Lead Life Maintenance Malignant Neoplasms Mammals Mediating Molecular Nuclear Outcome Pathway interactions Play Protein Biochemistry Protein Dynamics Proteins Publishing Refractory Regulation Repetitive Sequence Role System Testing Work Yeasts animal tissue cancer therapy cellular imaging chromatin protein combat experience fly homologous recombination human disease improved insight irradiation mutant recombinational repair repaired research study response tissue culture tissue/cell culture tool tool development tumor progression

项目摘要

DESCRIPTION (provided by applicant): The goal of this project is to understand how DNA repair mechanisms contribute to genome stability within the heterochromatic regions of the genome. Replication, repair and recombination of repeated DNAs can result in chromosome rearrangements and other types of genome instability, which are associated with cancer progression and other human diseases. Using the Drosophila model system, we have shown that 1) chromatin proteins required for heterochromatin establishment and maintenance are required to preserve the stability of repeated sequences, 2) heterochromatin undergoes a dramatic expansion immediately after irradiation, 3) repair of damage in heterochromatin requires the homologous recombination (HR) pathway, and 4) early steps in HR repair occur within the heterochromatin domain, but late events only occur after foci associated with repeated sequences translocate outside the heterochromatin domain. Our working hypothesis is that the potentially damaging consequences of HR repair of repeated sequences are avoided by the unusual spatial and temporal dynamics of heterochromatin repair, which are mediated by heterochromatin components. We propose to use Drosophila animals and tissue culture cells to identify the molecules and mechanisms that regulate the response to DNA damage in heterochromatic, repeated sequences. Specifically, we will use a combination of live and fixed cell imaging, mutant analysis, protein biochemistry, and genomic approaches to determine how heterochromatin expansion, repair foci dynamics, and homologous recombination are regulated at repeated DNAs, and how these events contribute to genome stability. The results of these studies will greatly improve our understanding of how the heterochromatin environment ensures the stability of repeated sequences, which has important applications to the diagnosis and treatment of human diseases.

描述（由申请人提供）：该项目的目标是了解 DNA 修复机制如何促进基因组异染色质区域内的基因组稳定性。重复DNA的复制、修复和重组可能导致染色体重排和其他类型的基因组不稳定，这与癌症进展和其他人类疾病有关。使用果蝇模型系统，我们表明：1）异染色质建立和维持所需的染色质蛋白需要保持重复序列的稳定性，2）异染色质在辐射后立即经历急剧扩张，3）异染色质损伤的修复需要同源重组 (HR) 途径，4) HR 修复的早期步骤发生在异染色质域内，但晚期事件仅在与重复序列相关的病灶易位到异染色质域外之后发生。我们的工作假设是，重复序列的 HR 修复的潜在破坏性后果可以通过异染色质修复的异常空间和时间动力学来避免，而异染色质修复是由异染色质成分介导的。我们建议使用果蝇动物和组织培养细胞来鉴定调节异染色质重复序列中 DNA 损伤反应的分子和机制。具体来说，我们将结合使用活细胞和固定细胞成像、突变分析、蛋白质生物化学和基因组方法来确定重复 DNA 中异染色质扩展、修复灶动力学和同源重组如何受到调节，以及这些事件如何促进基因组稳定性。这些研究结果将极大地提高我们对异染色质环境如何保证重复序列稳定性的理解，这对人类疾病的诊断和治疗具有重要的应用。