Regulation of chromosome cohesion during cell cycle progression

细胞周期进程中染色体凝聚力的调节

• 批准号: 10318566
• 负责人: Susannah Rankin
• 金额: $ 36.71万
• 依托单位: OKLAHOMA MEDICAL RESEARCH FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10318566
• 关键词: Acetylation; Acetyltransferase; Active Sites; Address; Architecture; Binding; Biochemical; Biochemistry; Biological; CCCTC-binding factor; Cell Culture Techniques; Cell Cycle; Cell Cycle Progression; Cell Nucleus; Cell division; Cells; Chromatin; Chromatin Structure; Chromosome Cohesion; Chromosome Segregation; Chromosome Structures; Chromosomes; Complex; Cues; Cultured Cells; DNA Damage; DNA Double Strand Break; DNA Repair; DNA biosynthesis; DNA replication fork; Data; Development; Ensure; Enzymes; Event; Family; Family member; Gene Expression Regulation; Genome; Genomic approach; Goals; Immobilization; Interphase; Maintenance; Modeling; Modification; Molecular; Mutation; Nuclear; Nuclear Structure; Outcome; Phenotype; Phosphorylation; Play; Poly(ADP-ribose) Polymerases; Proteins; Rana; Regulation; Role; Series; Signal Pathway; Signal Transduction; Sister Chromatid; Site; Structure; Testing; Time; Vertebrates; Work; Xenopus; chromatin immunoprecipitation; cohesin; cohesion; developmental disease; egg; experimental study; functional genomics; member; prevent; protein complex; recruit; response; segregation; tumorigenesis

In metazoans, the cohesin complex plays critical roles in many fundamental aspects of genome structure and maintenance. It ensures the accurate alignment and segregation of the products of DNA replication during cell division by tethering them together as they are made. It also promotes normal packaging of chromosomes into the interphase nucleus, both before and after DNA replication, which in turn ensures proper gene regulation. Finally, cohesin promotes DNA repair following both sporadic and programmed DNA double strand breaks. But how are these distinct activities of the cohesin complex controlled and integrated to ensure maintenance of sequence and structural integrity? This fundamental question is the basis for the experiments in this proposal. The association of cohesin with chromatin is dynamic: cohesin activity at a particular time and place reflects the collective outcome of both pro- and anti-cohesive activities. Changes in cohesin stability or chromatin binding occur in response to cell cycle progression, DNA damage signaling, and in response to certain developmental cues. In many cases, however, the signaling pathways that result in changes in cohesin binding are poorly understood. Modification of the Smc3 subunit of cohesin by members of the Eco1 family of acetyltransferases stabilizes the interaction of cohesin with chromatin. In vertebrates, there are two members of this family, Esco1 and Esco2, which we have shown play distinctly different roles in cohesin regulation. Esco2 is essential for establishing sister chromatid cohesion during DNA replication, while Esco1 modulates cohesin in its role in promoting normal chromosome architecture. With the experiments described here we will define how these two enzymes are regulated to generate very different outcomes using similar catalytic activity. In this proposal I describe a series of experiments using cell culture models, biochemistry, and functional analysis in Xenopus egg extracts to define how Esco1 and Esco2 are regulated to perform their unique functions. In Aim 1, we will define the molecular basis for the association of Esco2 with the replication apparatus. In Aims 2 and 3, we will define how chromatin structure is regulated by Esco1, and the impact of this regulation on DNA repair. In Aim 4 we will define how Esco1 impacts chromosome structure by analyzing nuclear assembly in G1. These experiments will elucidate in mechanistic detail how cohesin function is entrained by DNA replication and cell cycle progression to ensure proper sister chromatid tethering and a functional genomic landscape in interphase nuclei.

在后生动物中，粘着蛋白复合体在基因组结构的许多基本方面起着关键作用， 上维护它确保了细胞内DNA复制产物的精确排列和分离， 把它们分开，就像它们被制造出来一样。它还促进染色体的正常包装， 在DNA复制之前和之后的间期核，这反过来又确保了适当的基因调控。 最后，粘着蛋白促进DNA修复后，偶发性和程序性DNA双链断裂。但 如何控制和整合这些不同的内聚蛋白复合体活动，以确保维持 序列和结构完整性这个基本问题是本提案中实验的基础。 粘着蛋白与染色质的结合是动态的：在特定时间和地点的粘着蛋白活性反映了 这是支持和反对凝聚力活动的共同结果。粘着蛋白稳定性或染色质的变化 结合发生在响应细胞周期进程、DNA损伤信号传导和响应某些 发展线索然而，在许多情况下，导致粘附素结合变化的信号通路 我们对此知之甚少。Eco 1家族成员对粘附素Smc 3亚基的修饰 乙酰转移酶稳定了粘着蛋白与染色质的相互作用。在脊椎动物中， Esco 1和Esco 2在这个家族中，我们已经证明它们在粘附素调节中发挥着明显不同的作用。 Esco 2是在DNA复制过程中建立姐妹染色单体凝聚力所必需的，而Esco 1调节 在促进正常染色体结构中的作用。通过这里描述的实验，我们将 定义这两种酶是如何被调节的，从而使用相似的催化活性产生非常不同的结果。 在这个建议中，我描述了一系列的实验，使用细胞培养模型，生物化学，和功能， 分析非洲爪蟾卵提取物，以确定Esco1和Esco2是如何调节的，以执行其独特的功能。 功能协调发展的在目标1中，我们将定义Esco2与复制相关的分子基础。 设备.在目标2和3中，我们将定义Esco 1如何调节染色质结构，以及 这种对DNA修复的调节。在目标4中，我们将通过分析Esco1如何影响染色体结构来定义它。 核反应堆G1这些实验将详细阐明粘着蛋白功能是如何 由DNA复制和细胞周期进程携带，以确保适当的姐妹染色单体束缚和 间期核的功能基因组景观。