POLO KINASES IN CELL PROLIFERATION AND DEVELOPMENT

描述（来自应用程序）：蛋白激酶的波罗家族现在是 在扩散中起着关键作用。在高等真核生物中， 和酵母波罗激酶同源物对于细胞周期进程至关重要 M阶段。在哺乳动物中，不同的波罗激酶-例如Snk-也是 在细胞周期早期表达。哺乳动物的酶，特别是Plk和 Snk是本申请中提出的研究重点。除了 在催化激酶结构域中，波罗激酶具有保守序列， C-末端，表示波罗盒。波罗盒突变破坏了 在野生型Plk中观察到的定位和妥协的Plk有丝分裂功能。 波罗盒相互作用蛋白将被鉴定，它们的潜力， 影响中心体生物发生和功能，以及septin定位 组织，将被确定。 将通过筛选进行Snk和Plk底物的一般搜索 表达文库，并通过工程改造这些酶以获得 利用其他激酶不能有效利用的ATP类似物。在 为了更精确地描述Snk功能，胚胎干细胞将 通过靶向基因破坏来产生。这些细胞将用于 获得具有生殖系传播的小鼠，以确定其潜在作用 Snk在胚胎发育中的作用。 这些研究与癌症有直接的关系，因为癌症的有序分离， 染色体到两个子细胞需要未受损的Plk功能。直到 最近，非整倍体，癌细胞中的一种状态， 染色体数目异常，被认为是一个后果，而不是一个 因为，恶性肿瘤。然而，最近的研究表明，非整倍体可以导致 癌中心体在维持细胞的完整性中起着重要的作用 人类基因组。异常中心体结构和非整倍体与染色体畸变密切相关。 与晚期肿瘤相关。这里提出的研究解决了分子 由Plk控制的事件，涉及中心体复制和启动 卵裂沟的形成和Snk影响这些和其他的潜力 特定细胞类型的事件。

DESCRIPTION (from the application): The polo family of protein kinases is now known to have a critical role in proliferation. In higher eukaryotes, flies, and yeast polo kinase homologues are essential for cell cycle progression through M phase. In mammals, distinct polo kinases -for example, Snk-are also expressed early in the cell cycle. The mammalian enzymes, particularly Plk and Snk are the focus of the studies proposed in this application. IN addition to the catalytic kinase domain, polo kinases have a conserved sequence in the C-terminus, denoted the polo box. Polo box mutations disrupt the cellular localization observed with wild-type Plk and compromise Plk mitotic functions. Polo box interacting proteins will be identified and their potential to influence centrosome biogenesis and function, as well as septin localization and organization, will be determined. A general search for Snk and Plk substrates will be conducted by screening expression libraries and by engineering these enzymes to attain the capacity to utilize ATP analogues that will not be used efficiently by other kinases. In order to more precisely characterize Snk functions, embryonic stem cells will be generated with a targeted gene disruption. These cells will be used to obtain mice with germline transmission in order to determine the potential role of Snk in embryonic development. These studies have direct relevance to cancer, as the ordered segregation of chromosomes to two daughter cells requires unimpaired Plk function. Until recently, aneuploidy, the condition in cancer cells in which they display an abnormal number of chromosomes, was considered a consequence, rather than a cause, of the malignancy. However, recent studies suggest aneuploidy can cause cancer. Centrosomes play a critical role in the maintainance of the integrity of the human genome. Aberrant centrosome structure and aneuploidy are tightly correlated in advanced tumors. The studies proposed here address the molecular events controlled by Plk involving centrosome duplication and initiation of cleavage furrow formation and the potential of Snk to influence these and other events in specific cell types.