DNA Damage & DNA Replication: a Complex Relationship

项目摘要/摘要 我们的首要目标是：i.确定mre11复合体激活ATM的机制(S)；ii.至 确定mre11复合体在DNA复制中的作用(S)；界定Mre11情结在中国的作用(S) 对DNA复制压力的反应。作为强调DNA复制压力的一部分，我们的重点包括 RTEL1，其作用是减轻端粒的复制压力。酵母和老鼠基因的结合， 生物化学和结构生物学被用来解决这些问题。我们以前在这些主题上的工作 导致了实质性的科学进步和对与人类健康相关的过程的洞察。特定领域 调查的范围包括： ·酵母中的遗传筛选和对癌症基因组数据的挖掘显示功能Rad50的分离 影响ATM依赖的DNA损伤信号而不影响DNA修复功能的突变 Mre11复合体。这些突变构成了破译机制的资源，通过这种机制 Mre11复合体激活ATM激酶，启动DNA损伤信号。 ·我们已经在小鼠身上建立了三个复发的肿瘤携带突变的模型，这些突变被证实是 用于ATM激活的亚型但精通DNA修复。这些动物模型提供了独特的 描述依赖于Mre11复合体的ATM功能的机会。 ·我们已经确定了在DNA复制叉处发挥作用的因素，其方式取决于 Mre11复合体。我们实验室的一个重要重点是了解这些人的功能作用(S) 各种因素。促进准确DNA复制的因子中的缺陷与人类高度相关 因此，了解这一基本过程是我们工作中的一个重要优先事项。 ·虽然mre11复合体在复制分叉起作用，但RTEL1是一个解旋酶，它促进 端粒DNA的精确复制。我们已经发现RTEL1影响丰度和 从亚端粒区转录而来的称为Terra的长非编码RNA的处置 在所有真核生物中。我们在这方面的工作有两个目标。首先，理解RTEL1的作用 来维持端粒的稳定性。其次，利用这些信息来阐明 这是一个长期存在的问题。

PROJECT SUMMARY/ABSTRACT Our overarching goals are: i. to define the mechanism(s) of ATM activation by the Mre11 complex; ii. to define the role(s) of the Mre11 complex in DNA replication; iii. To define the role(s) of the Mre11 complex in response to DNA replication stress. As part of the emphasis of DNA replication stress, our focus includes RTEL1 which acts to mitigate replication stress at the telomere. A combination of yeast and mouse genetics, biochemistry, and structural biology are employed to address these issues. Our previous work on these topics led to substantial scientific progress and insight regarding processes relevant to human health. Specific areas of inquiry are: • Genetic screens in yeast and mining of cancer genomic data revealed separation of function Rad50 mutations that affect ATM dependent DNA damage signaling without affecting the DNA repair functions of the Mre11 complex. These mutations constitute a resource for deciphering the mechanism by which the Mre11 complex activates the ATM kinase to initiate DNA damage signaling. • We have modeled three recurrent tumor borne mutations in mice that were confirmed to be hypomorphic for ATM activation but proficient in DNA repair. These animal models offer a unique opportunity to delineate Mre11 complex-dependent ATM functions. • We have identified factors that function at the DNA replication fork in a manner that depends on the Mre11 complex. An important focus of our laboratory is to understand the functional role(s) of those factors. Defects in factors that promote accurate DNA replication are highly correlated with human disease, and so understanding this fundamental process is an important priority in our work. • Whereas the Mre11 complex functions at the replication fork, RTEL1 is a helicase that promotes accurate replication of telomeric DNA. We have discovered that RTEL1 influences the abundance and disposition of a long non coding RNA, called TERRA, that is transcribed from the subtelomeric regions of all eukaryotes. Our goal in this aspect of our work is two fold. First, to understand the role of RTEL1 in maintaining telomere stability. Second, to use that information to shed light on the function of TERRA, which is a long standing question.