Drosophila MCM10 in DNA replication and Heterochromatin formation

描述(申请人提供)：癌症由许多特定的疾病状态组成，所有这些状态都有共同之处：无规律的生长，分化失败，以及染色体生物学上的缺陷。染色体生物学上的缺陷和细胞的无节制生长往往是DNA复制机制的错误调节和/或突变的结果。然而，越来越明显的是，癌症不仅仅是由经典突变驱动的，而且还由表观遗传变化启动和维持。表观遗传改变是与基因组的核苷酸序列无关的改变，而是导致基因表达改变的核苷酸和DNA相关蛋白质的改变。这种表达的改变通常是DNA以异染色质形式紧密堆积形成的结果。分开来看，DNA复制和异染色质形成都是癌症生物学的重要方面。了解这两个过程对于我们理解和治疗癌症非常重要。了解这两个过程是如何联系在一起的，有望为我们正在进行的抗击癌症的努力增加一个新的和有用的方面。这项提议的核心目的是通过对果蝇Mcm10的研究，开始阐明DNA复制和异染色质形成是如何联系在一起的。在这个水平上研究这种蛋白质，我们就可以开始了解DNA复制和异染色质形成之间的相互作用网络。利用最新可用的技术，我们将识别MCM10的多个等位基因，这将使MCM10在DNA复制和染色质生物学方面的功能分离成为可能。将这些角色分开分析可能会导致治疗癌症的新疗法和诊断方法。为此，我们建议使用易处理的遗传系统黑腹果蝇来探索以下假设：果蝇DNA复制因子MCM10在DNA复制和染色质动力学中具有分离的功能。我们将通过以下具体目标来解决这一假设：1.鉴定和表征果蝇MCM10的突变体2.检测MCM10等位基因对DNA复制的影响3.检测MCM10等位基因对染色体形态和细胞周期的影响4.分析MCM10等位基因对异染色质形成的影响5.确定这些MCM10等位基因对与其他蛋白质相互作用的影响 与公共健康相关：了解DNA如何适当包装和DNA如何复制之间的联系，将提供对人类癌症如何发展的更广泛理解。揭示这些基本过程是如何联系在一起的细节将为癌症的诊断和治疗提供信息。

DESCRIPTION (provided by applicant): Cancer consists of a multitude of specific disease states, all of which share in common: unregulated growth, failure to differentiate, and defects in chromosome biology. Defects in chromosomal biology and unregulated growth of cells are often the result of mis-regulation and/or mutations of the DNA replication machinery. However, it is becoming increasingly apparent that cancer is not driven solely by classical mutation but is also initiated and maintained by epigenetic changes. Epigenetic changes are alterations not associated with the nucleotide sequence of the genome but rather modifications of the nucleotides and DNA associated proteins that result in altered expression of genes. This altered expression is often the result of the formation of tightly packed DNA in the form of heterochromatin. Taken separately, both DNA replication and heterochromatin formation are important aspects of cancer biology. Understanding these two processes has been important for our understanding and treatment of cancer. Understanding how these two processes are linked promises to add a new and useful dimension to our ongoing efforts to confront cancer. The core aim of this proposal is to begin spell out how DNA replication and heterochromatin formation are linked through the study of Drosophila Mcm10. Study of this proteins on this level we allow us to begin to understand the network of interactions between DNA replication and heterochromatin formation. Using newly available technologies we will identify multiple alleles of MCM10 which will enable the separation of MCM10 function with respect to DNA replication and chromatin biology. Parsing these roles apart has the potential to lead to new therapies and diagnostics in treating cancer. Toward this end we propose to use the tractable genetic system Drosophila melanogaster to explore the following hypothesis: The Drosophila DNA replication factor MCM10 has separable functions in DNA replication and chromatin dynamics. We will address this hypothesis through the following specific aims: 1. Identify and characterize mutants in Drosophila MCM10 2. Assay MCM10 alleles for impacts on DNA replication 3. Assay MCM10 alleles for impacts on chromosome morphology and cell cycle 4. Assay the consequences of the MCM10 alleles on heterochromatin formation 5. Determine the consequences of these MCM10 alleles on interactions with other proteins PUBLIC HEALTH RELEVANCE: Understanding the link between how DNA is packaged appropriately and how DNA is copied will provide a broader understanding of how cancer develops in humans. Revealing the details of how these essential processes are linked will inform the diagnosis and treatment of cancer.