Germline mutagenesis at meiotic double-strand breaks

减数分裂双链断裂处的种系突变

• 批准号: 10720403
• 负责人: Maria Jasin
• 金额: $ 44.92万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-08 至 2028-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10720403
• 关键词: Address; Adolescent; Affect; Architecture; Binding; Binding Sites; Biological Assay; Cell division; Cells; Chromosomal translocation; Chromosomes; Circular DNA; DNA; DNA Double Strand Break; DNA Sequence Rearrangement; Detection; Development; Distant; Ensure; Event; Evolution; Excision; Frequencies; Generations; Genes; Genetic Recombination; Genome; Genomic Segment; Germ Cells; Haploidy; Health; Homologous Gene; Human; Lesion; Maps; Meiosis; Meiotic Recombination; Mitotic; Mus; Mutagenesis; Mutant Strains Mice; Mutation; Nonhomologous DNA End Joining; Outcome; Paternal Age; Preparation; Prevalence; Publishing; Regulation; Resected; Risk; Role; SPO11 gene; Single-Stranded DNA; Somatic Cell; Spermatogenesis; Spo11 protein; Yeasts; age effect; aged; ataxia telangiectasia mutated protein; base; egg; experience; experimental study; genome-wide; homologous recombination; in vivo; male; repaired; segregation; sperm cell; transmission process; young adult

Project Summary/Abstract Meiotic recombination is essential for the reductional cell division in mammalian germ cells and thus for the development of haploid gametes, i.e., sperm and eggs. Recombination is initiated by hundreds of DNA double- strand breaks (DSBs) introduced genome-wide that are catalyzed by the SPO11 protein. Faithful transmission of the genome to subsequent generations requires proper repair of these numerous DSBs, primarily through recombination with the homolog. DSB formation is regulated in meiotic cells by the ATM kinase, which is known to be a primary responder to DSBs in mitotic cells, such that in the absence of ATM, meiotic DSBs increase ~10-fold. We recently discovered that meiotic DSBs are at risk for provoking germline rearrangements, in particular deletions and tandem duplications involving nonhomologous end-joining, especially in the absence of ATM. These events are consequential in terms of disrupting the genes in which these hotspots occur as well as the associated PRDM9 binding sites that govern recombination at those loci. Thus, our findings reveal a previously hidden potential for germline mutagenesis that is likely to affect human health and genome evolution. In humans, recent long-range sequencing of Icelanders supports this impact. This proposal pursues aims to understand the mechanisms that give rise to these events, the range of events at meiotic DSBs, and the effect of age. We hypothesize that other rearrangements are possible at meiotic DSBs than what we have previously identified. Thus, in the first aim, we propose to determine the range of mutagenic outcomes that can arise from meiotic DSBs, including long-range deletions and duplications and chromosomal translocations. In the second aim, we examine factors that may impact the formation of deletions. We focus on the effect of DNA end processing at two steps, SPO11 removal and end processing, and recombination. Further, we address whether gaps formed at nearby DSBs are substrates for homologous recombination and the impact of paternal age in the rearrangement events at meiotic DSBs.

项目摘要/摘要 减数分裂重组对于哺乳动物生殖细胞的还原细胞分裂至关重要，因此 单倍配子的发展，即精子和卵。重组是由数百个DNA双重的 链断裂（DSB）引入了由Spo11蛋白催化的全基因组。忠实的传播 基因组到随后的几代需要正确修复这些众多DSB，主要是通过 与同源物重组。 DSB的形成是由ATM激酶在减数分裂细胞中调节的，即 已知是有丝分裂细胞中DSB的主要响应者，因此在没有ATM的情况下，减数分裂DSB 增加约10倍。 我们最近发现，减数分裂DSB有挑衅种系重排的风险， 特定的删除和串联重复，涉及非同源最终结合，尤其是在没有的情况下 ATM。在破坏这些热点的基因方面，这些事件也是如此 作为控制这些基因座重组的相关PRDM9结合位点。因此，我们的发现揭示了 以前隐藏的种系诱变潜力可能会影响人类健康和基因组 进化。在人类中，最近对冰岛人的远程测序支持了这一影响。该建议追求 旨在了解引起这些事件的机制，减数分裂DSB的一系列事件以及 年龄的影响。我们假设在减数分裂DSB上可能还可以进行其他重排比我们拥有的重排 先前确定的。因此，在第一个目的中，我们建议确定可以 由减数分裂的DSB产生，包括远程缺失，重复和染色体易位。在 第二个目的，我们研究可能影响缺失形成的因素。我们专注于DNA的效果 在两个步骤中进行结束处理，即SPO11去除和结束处理以及重组。此外，我们解决 在附近DSB上形成的差距是否是同源重组的底物和父亲的影响 减数分裂DSB的重排活动的年龄。