Genetic Recombination of c. Elegans

基因重组 C.

• 批准号: 8523907
• 负责人: ANNE M VILLENEUVE
• 金额: $ 31.78万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8523907
• 关键词: Aneuploidy; Architecture; Biological Assay; Caenorhabditis elegans; ChIP-seq; Chromosome Pairing; Chromosome Segregation; Chromosomes; Collaborations; Complex; Congenital Abnormality; DNA; DNA Double Strand Break; Defect; Detection; Ensure; Equilibrium; Event; Excision; Failure; Genetic; Genetic Crossing Over; Genetic Recombination; Genetic Screening; Genome; Germ Cells; Goals; Homologous Gene; Human; Karyotype; Life; Location; Maintenance; Mediating; Meiosis; Mitogen Activated Protein Kinase 1; Modification; Nematoda; Optic Chiasm; Organism; Outcome; Pathway interactions; Phosphorylation; Process; Prophase; Protein Region; Proteins; Psychological reinforcement; Regulation; Residual state; Role; Sister Chromatid; Site; Spontaneous abortion; Synaptonemal Complex; System; Testing; Time; Variant; Work; base; design; genome-wide; in vivo; mutant; next generation; repaired; response; segregation; tool

DESCRIPTION (provided by applicant): Our long term goal is to understand how genetic recombination contributes to the faithful inheritance of chromosomes. Genetic recombination is of central importance to sexually reproducing organisms, since crossover recombination events between the DNA molecules of homologous chromosomes, and the resulting chiasmata, are necessary for proper chromosome segregation at the meiosis I division. Failure to form crossovers leads to chromosome missegregation and consequent aneuploidy, one of the leading causes of miscarriages and birth defects in humans. Meiotic crossing over is accomplished by deliberate induction of double-strand DNA breaks (DSBs), followed by repair of these breaks using meiosis-specific modifications of DSBR pathways in the context of meiosis-specific chromosome architecture. This process is subject to multiple levels of regulation to ensure that DSBs are formed and repaired in an appropriate temporal context, both to avoid posing a threat to genome integrity and to guarantee that each chromosome pair will undergo the obligate crossover required to promote homolog segregation. We are investigating the mechanisms that promote and limit the formation of interhomolog crossovers (COs) and that regulate DSB formation in the nematode C. elegans, a simple metazoan organism that is especially amenable to combining sophisticated cytological and genetic approaches in a single experimental system, and in which robust crossover control mechanisms are known to operate. The proposed work will exploit recent advances that provide the means to visualize the sites of nascent meiotic CO events in both live and fixed germ cells using GFP:COSA-1, to screen directly for mutants with impaired CO interference, to experimentally induce recombination events at defined sites and/or defined time frames, to target recombination proteins to defined sites, and to capture DNA associated with CO sites. One major goal is to identify factors and mechanisms that contribute to CO interference, and to understand the interplay between mechanisms that antagonize CO formation and mechanisms that promote CO designation and progressive differentiation of CO sites. A related goal is to uncover features that may bias the outcome of CO/NCO designation. Another goal is to understand the basis of dynamic regulation of repair partner utilization during meiotic progression. Finally, we will analyze the architecture of the meiotic DSB regulation network to understand how DSB formation is modulated to maintain a balance between the beneficial effects of COs and the potential harmful consequences of the process by which they are generated.

描述（由申请人提供）： 我们的长期目标是了解基因重组如何有助于染色体的忠实遗传。遗传重组对有性生殖生物体至关重要，因为同源染色体的DNA分子之间的交叉重组事件以及由此产生的交叉对于减数分裂I分裂时的适当染色体分离是必要的。未能形成交叉导致染色体错误分离和随之而来的非整倍体，这是人类流产和出生缺陷的主要原因之一。减数分裂交换是通过故意诱导双链DNA断裂（DSB），然后在减数分裂特异性染色体结构的背景下使用减数分裂特异性修饰DSBR途径修复这些断裂来完成的。这一过程受到多层次的调控，以确保DSB在适当的时间背景下形成和修复，既避免对基因组完整性构成威胁，又保证每个染色体对将经历促进同源物分离所需的专性交叉。我们正在研究的机制，促进和限制形成的同源交叉（CO），并调节DSB的形成在线虫C。elegans，一种简单的后生动物，特别适合于在单一实验系统中结合复杂的细胞学和遗传学方法，并且已知在其中操作稳健的交叉控制机制。拟议的工作将利用最新的进展，提供可视化的手段，在活的和固定的生殖细胞中的新生减数分裂CO事件的网站使用GFP：COSA-1，直接筛选受损的CO干扰的突变体，实验诱导重组事件在定义的网站和/或定义的时间范围内，目标重组蛋白到定义的网站，并捕获与CO网站相关的DNA。一个主要的目标是确定因素和机制，有助于CO干扰，并了解拮抗CO形成的机制和机制，促进CO指定和渐进分化的CO网站之间的相互作用。一个相关的目标是发现可能会导致CO/NCO指定结果偏差的特征。另一个目标是了解在减数分裂进程中修复伴侣利用的动态调节的基础。最后，我们将分析减数分裂DSB调控网络的结构，以了解如何调节DSB的形成，以保持CO的有益影响和产生它们的过程的潜在有害后果之间的平衡。