Fidelity of Repair within Repetitive DNA

这项建议侧重于伴随着发芽酵母DNA修复的几个突变变化。脱氧核糖核酸 修复是由半乳糖调节的位点特异性HO内切酶的表达诱导的，创建了一个单一的 双链断裂(DSB)。一个主要目标是了解与模板相关的复杂突变 在基因转换过程中发生的转换。将研究两种类型的修复：1.拟回文修复 基因转化过程中的突变形成和2.染色体间微同源性介导的模板 在基因转换过程中的切换。将对解旋酶和其他修复因子进行遗传分析，以 寻找控制这两个事件水平的蛋白质，并探索染色质的作用。一个 第二个目标是了解基因转化过程中重复拷贝数的变化，这是由我们的 最近发现DSB断裂修复和缺口修复之间的重要区别。与 Mitch McVey，该计划项目的另一位成员，专注于果蝇DSB修复，我们将 评估导致重复序列之间缺失的流产缺口修复的频率 复制的区域。

This proposal focuses on several mutational changes accompanying DNA repair in budding yeast. DNA repair is induced by galactose-regulated expression of the site-specific HO endonuclease, creating a single double-strand break (DSB). One major goal is to understand complex mutations associated by template switching that occur during gene conversion. Two types of repair will be studied: 1. Quasipalindrome mutation formation during gene conversion and 2. Interchromosomal microhomology-mediated template switching during gene conversion. Genetic analysis of helicases and other repair factors will be screened to find proteins that control the level of these two events, along with an exploration of the role of chromatin. A second goal is to understand changes in repeat copy number during gene conversion, motivated by our recent discovery of important differences between DSB break repair and gap repair. In collaboration with Mitch McVey, another member of this Program Project who focuses on DSB repair in fruit flies, we will assess the frequency of abortive gap repair leading to deletions between repeated sequences within the copied region.