Aurora B kinase is the downstream target of ATR

描述（由申请人提供）：在细胞周期中，DNA精确复制和分离的中断会导致基因组不稳定和染色体错误分离。基因组不稳定性长期以来被认为是正常细胞转化为肿瘤细胞的重要步骤。最近，一种异常的染色体表型被描述为在整个染色体的复制时间（DRT）中存在延迟。具有DRT的染色体已被证明是不稳定的，并有助于基因组的不稳定。DRT染色体显示有丝分裂特异性丝氨酸10上组蛋白H-3磷酸化的延迟和有丝分裂染色体凝聚（DMC）的延迟。H-3磷酸化已被证明是染色体凝聚和分离的重要步骤。Aurora B激酶被认为是H-3磷酸化的原因。Thayer实验室最近的研究结果表明，DRT染色体通过ATR激活复制检查点途径。因此，我假设抑制极光B，无论是通过抑制激酶活性还是抑制染色体募集，在DMC表型中起直接作用。目的是表征DRT/DMC，复制检查点和Aurora B激酶之间的联系。

DESCRIPTION (provided by applicant): Disruptions in accurate DNA replication and segregation during the cell cycle results in genomic instability and missegregation of chromosomes. Genomic instability has long been recognized as an important step in converting normal cells into neoplastic cells. Recently, an abnormal chromosomal phenotype has been described whereby there is a delay in the replication timing (DRT) of an entire chromosome. Chromosomes with DRT have been shown to be unstable and contribute to genomic instability. DRT chromosomes show a delay in the mitosis-specific phosphorylation of histone H-3 on serine 10 and a delay in mitotic chromosome condensation (DMC). H-3 phosphorylation has been shown to be an important step in chromosome condensation and segregation. Aurora B kinase is thought to be responsible for the phosphorylation of H-3. Recent results from the Thayer lab have shown that DRT chromosomes activate the replication checkpoint pathway via ATR. Therefore, I hypothesize that inhibition of Aurora B, either by inhibition of kinase activity or inhibition of recruitment to the chromosome, plays a direct role in the DMC phenotype. The objective is to characterize the link between DRT/DMC, the replication checkpoint, and Aurora B kinase.