Chromosome Inheritance

染色体遗传

• 批准号: 8234410
• 负责人: BRUCE W. STILLMAN
• 金额: $ 60.89万
• 依托单位: COLD SPRING HARBOR LABORATORY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8234410
• 关键词: Anaphase; Animal Model; Binding; Boxing; Breast; Breast Cancer Cell; CDC6 gene; CDK2 gene; Cancer Control; Cell Aging; Cell Cycle; Cell Death; Cell Proliferation; Cell Therapy; Cell physiology; Cells; Centrioles; Centromere; Centrosome; Characteristics; Chromosome Segregation; Chromosome Structures; Chromosomes; Complex; Cyclin A; Cyclin E; Cytokinesis; DNA; DNA biosynthesis; DNA replication origin; Defect; Drosophila genus; E2F Transcription Factor 1; E2F1 gene; Elements; Ensure; Environment; G1 Phase; Gene Expression; Genes; Genetic; Genome; Genome Stability; Goals; Heterochromatin; Human; Human Genome; In Vitro; Instruction; Kinetochores; Laboratories; Location; Maintenance; Malignant Neoplasms; Mammary Neoplasms; Metaphase; Methods; Microtubules; Mitosis; Mitotic; Mus; Mutation; NCI Center for Cancer Research; Nature; Normal Cell; Nuclear; Organism; Phase; Phosphorylation; Phosphotransferases; Play; Process; Proliferating; Prophase; Proteins; Proteomics; RNA Helicase; Replication Initiation; Research; Roche brand of trastuzumab; Role; S Phase; Signal Transduction; Simian virus 40; Site; Testing; Time; Tissues; Trastuzumab; Work; Yeasts; base; cancer cell; cancer therapy; chromatin protein; insight; malignant breast neoplasm; neoplastic cell; next generation; origin recognition complex; protein complex; reconstitution; research study; segregation; therapeutic target; tumor; tumor xenograft

PROJECT SUMMARY (See instructions): Cancer involves the induction of uncontrolled DNA replication and mitosis in cells, as well as processes that ensure cells evade cell death or senescence and survive in specific tissue micro-environments. Project 1 has been a leader in studying the mechanisms and control of inheritance of the human genome and has identified many of the key proteins that are involved in DNA synthesis at the replication fork and other proteins that are involved in the initiation of DNA replication. In the proposed studies. Project 1 will continue to focus on how the initiation of DNA replication is controlled in human cells and how this process goes awry in tumor cells. Specific Aim 1 will focus on how the origins of DNA replication are marked in chromosomes so that they can form pre-replicative complexes during exit from mitosis or during Gl phase, thereby enabling the initiation of DNA replication in S phase of the cell division cycle. Since the Origin Recognition Complex, particularly its largest subunit Orel is loaded onto chromosomes beginning in prophase of mitosis and Orel is the most stably bound chromatin protein, the locations within the human genome for Orel binding will be determined. In addition, proteins that dynamically interact with ORC during M and G1 phases will be determined. The cell cycle regulators Cyclin E-CDK2 and Cyclin A-CDK2, the former often over-active in breast cancer, are controlled by direct interactions with Orel and Cdc6 and how these interactions influence the initiation of DNA replication and centriole duplication in centrosomes will be investigated. Recent evidence has emerged that ORC subunits play a critical role at kinetochores that bind microtubule spindles for congression of chromosomes prior to their segregation. In Specific Aim 2, interactions between the Orc2 and Orc3 subunits of ORC and the Spindle Assembly Checkpoint kinase BubRI will be investigated, as will the role of the ORC subunits in maintenance of stable spindle attachment during the metaphase to anaphase transition. In Specific Aim 3, the control of DNA replication by the DEAD-box RNA helicase DDX5 and its interaction with the transcription factor E2F1 will be studied. DDX5 is amplified in the genome of cells in 25% of human breast cancers and it is these cells that display selective sensitivity to inhibition of DDX5 protein levels. How DDX5 influences E2F1-driven expression of DNA replication genes in the Gl phase of the cell cycle will be investigated. Project 1 will also investigate how tumor cells with amplified copy number of DDX5 become addicted to its continued expression, in contrast to normal, non-tumor cells and many other cancer cells. Finally, the additive effects on inhibition of tumors cell proliferation with the combination of DDX5 depletion and Trastuzumab (Herceptin) treatment will be examined.

项目总结（见说明）： 癌症涉及诱导细胞中不受控制的DNA复制和有丝分裂，以及确保细胞逃避细胞死亡或衰老并在特定组织微环境中存活的过程。项目1一直是研究人类基因组遗传机制和控制的领导者，并已确定了许多参与复制叉和其他DNA合成的关键蛋白质。 参与DNA复制起始的蛋白质。在拟议的研究中。项目1将继续关注人类细胞中DNA复制的启动是如何控制的，以及这一过程在肿瘤细胞中是如何出错的。具体目标1将集中在如何在染色体中标记DNA复制的起点，以便它们可以在退出有丝分裂或G1期期间形成复制前复合物，从而使 在细胞分裂周期的S期启动DNA复制。由于起源识别复合物，特别是其最大亚基Orel在有丝分裂前期开始加载到染色体上，并且Orel是最稳定结合的染色质蛋白，因此将确定Orel结合在人类基因组内的位置。此外，还将确定在M期和G1期与ORC动态相互作用的蛋白质。细胞周期调节因子细胞周期蛋白E-CDK 2和细胞周期蛋白A-CDK 2，前者在乳腺癌中经常过度活跃，通过与Orel和Cdc 6的直接相互作用来控制，这些相互作用如何影响中心体中DNA复制和中心粒复制的起始将被研究。最近的证据表明，ORC亚基在结合微管纺锤体的着丝粒中起着关键作用，以便在分离前使染色体聚集。在特定目标2中，将研究ORC的Orc 2和Orc 3亚基与纺锤体组装检查点激酶BubRI之间的相互作用，以及ORC亚基在中期向后期过渡期间维持稳定纺锤体附着的作用。在特定目标3中，将研究DEAD盒RNA解旋酶DDX 5对DNA复制的控制及其与转录因子E2 F1的相互作用。DDX 5在25%的人类乳腺癌细胞的基因组中扩增，并且正是这些细胞对DDX 5蛋白水平的抑制显示出选择性敏感性。将研究DDX 5如何影响细胞周期的G1期中E2 F1驱动的DNA复制基因的表达。项目1还将研究与正常的非肿瘤细胞和许多其他癌细胞相比，DDX 5拷贝数扩增的肿瘤细胞如何对其持续表达上瘾。最后，将检查DDX 5消耗和曲妥珠单抗（赫赛汀）治疗组合对肿瘤细胞增殖抑制的累加效应。