Regulation of Chromosome Segregation in Human Cells

描述(由申请者提供)：这项资助的长期目标是阐明维持染色体分离准确性的分子和机制。这些信息对维持和改善人类健康至关重要，因为不准确的隔离会导致非整倍体，并导致唐氏综合症和癌症等疾病。为了便于剖析这一过程和其他复杂的生物学过程，我们的实验室开发了通过同源重组精确删除或修改人类体细胞中基因的新方法。通过将这些方法与高分辨率显微镜和化学遗传学相结合，我们已经确定了蛋白激酶Plk1(Polo-like kinase1)和Mps1的新功能和调控，它们是所有真核生物有丝分裂和细胞分裂的重要调节因子。基于我们的初步发现，下一个授权期提出了三个目标：(1)阐明依赖Plk1的中心体成熟的影响因素和机制；(2)测试MPS1的S对纺锤体组装检查点(SAC)胞质和动粒依赖的分支的贡献；(3)鉴定MPS1在SAC强制执行和染色体双向定位中介导激酶功能的底物。这些研究将阐明调节和维持人类高保真染色体分离的机制。这些信息对于了解正常细胞如何避免非整倍体及其对人类健康的不利影响，以及开发针对疾病背景下的非整倍体的新疗法至关重要。 公共卫生相关性：染色体分离的错误会导致非整倍体，这是一种与包括唐氏综合症和癌症在内的人类疾病密切相关的异常遗传结构。迫切需要在分子水平上阐明染色体分离是如何控制的，以降低正常细胞中非整倍体的可能性，并将非整倍体作为癌细胞的“阿喀琉斯之踵”。在下一个授权期，我们特别关注两个主要的激酶--Plk1和Mps1--在人类染色体分离中的作用。由于这些激酶在肿瘤中过度产生，并被评估为抗肿瘤治疗的靶点，我们的研究与正在进行的扩大和改进癌症药典的努力具有很强的相关性。

DESCRIPTION (provided by applicant): The long-term goal of this grant is to elucidate the molecules and mechanisms that sustain the accuracy of chromosome segregation. Such information is crucial for maintaining and improving human health, as inaccurate segregation causes aneuploidy and contributes to disorders like Down Syndrome and cancer. To facilitate the dissection of this and other complex biological processes, our laboratory has developed novel methods for precisely deleting or modifying genes in human somatic cells via homologous recombination. By combining these methods with high-resolution microscopy and chemical genetics, we have identified novel functions and regulation of the protein kinases Plk1 (Polo-like kinase 1) and Mps1, which are essential regulators of mitosis and cell division in all eukaryotes. Based on our preliminary findings, three aims are proposed for the next grant period: (1) to elucidate the effectors and mechanism of Plk1-dependent centrosome maturation; (2) to test Mps1's contribution to the cytosolic and kinetochore-dependent branches of the spindle assembly checkpoint (SAC); and (3) to identify the substrates of Mps1 that mediate the kinase's functions in SAC enforcement and chromosome bi-orientation. These studies will illuminate the mechanisms that regulate and sustain the high fidelity of chromosome segregation in humans. Such information is crucial for understanding how normal cells avoid aneuploidy and its adverse impacts on human health, and for developing novel treatments that specifically target aneuploidy in the context of disease. PUBLIC HEALTH RELEVANCE: Errors in chromosome segregation result in aneuploidy, an abnormal genetic configuration strongly associated with human disease, including Down Syndrome and cancer. There is a strong need to elucidate how chromosome segregation is controlled at the molecular level, both to reduce the likelihood of aneuploidy in normal cells, and to exploit aneuploidy as an "Achilles heel" in cancer cells. During the next grant period we focus specifically on the roles of two master kinases - Plk1 and Mps1 - in human chromosome segregation. As these kinases are overproduced in tumors and being evaluated as targets for anti-neoplastic therapy, our studies have strong relevance to ongoing efforts to expand and improve the cancer pharmacopeia.