Regulation of Chromosome Cohesion during Cell Cycle Progression

描述（由申请方提供）：DNA复制后，每条染色体的两个相同拷贝通过称为姐妹染色单体凝聚的过程保持在一起，直到细胞分裂。姐妹染色单体的凝聚力对于染色体的精确分离、DNA损伤的修复、转录程序的维持和正常发育是必不可少的。内聚基因的突变导致出生缺陷，并与某些癌症相关的基因组不稳定性有关。内聚失败被认为是与年龄相关的非整倍体卵子增加的基础，这是出生缺陷和自然流产的主要原因。 姐妹染色单体的凝聚是由一个大的蛋白质复合物称为凝聚。这种复合物的活性必须受到调节，以确保粘附素被放置在染色质上，并以与DNA复制和细胞周期进程整合的方式被激活。这种调节是通过几种蛋白质的活性来完成的，这些蛋白质合作调节粘着蛋白-染色质相互作用的稳定性。在这里，我们提出了一系列的实验，以确定如何这些蛋白质，我们称之为“凝聚稳定网络”，在DNA复制过程中，并在响应细胞周期的进展进行调节。使用生物化学和细胞生物学方法的组合，包括在培养的细胞和青蛙卵提取物的测定，我们将定义的cohesin复合物和这个监管网络之间的功能相互作用。这些实验的结果将提供关键的洞察力的机制，凝聚力的建立，维持和重塑脊椎动物系统。

DESCRIPTION (provided by applicant): Following DNA replication, the two identical copies of each chromosome are held together until cell division by a process referred to as sister chromatid cohesion. Sister chromatid cohesion is essential for accurate chromosome segregation, repair of DNA damage, the maintenance of transcriptional programs, and normal development. Mutations in cohesion genes lead to birth defects and are associated with genomic instability associated with certain cancers. Failures in cohesion are thought to underlie the maternal age-related increase in aneuploid eggs, a major cause of birth defects and spontaneous abortion. Sister chromatid cohesion is mediated by a large protein complex called cohesin. The activity of this complex must be regulated to ensure that cohesin is laid down on chromatin and activated in a way that is integrated with DNA replication and cell cycle progression. This regulation is accomplished by the activities of several proteins that cooperate to regulate the stability of the cohesin-chromatin interaction. Here we propose a series of experiments to define both how these proteins, which we dub the "cohesin stability network", are regulated during DNA replication and in response to cell cycle progression. Using a combination of biochemical and cell biology approaches, including assays in cultured cells and frog egg extracts, we will define the functional interactions between the cohesin complex and this regulatory network. The results of these experiments will provide critical insight into the mechanism by which cohesion is established, maintained, and remodeled in vertebrate systems.