MPS1 KINASE AND YEAST SPINDLE POLE CYCLE

MPS1 激酶和酵母纺锤体极周期

• 批准号: 6386060
• 负责人: MARK WINEY
• 金额: $ 27.57万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6386060
• 关键词: Saccharomyces cerevisiae; Schizosaccharomyces pombe; cell cycle; enzyme activity; fungal genetics; gene mutation; laboratory rabbit; nucleic acid hybridization; phosphorylation; protein kinase; spindle pole body; tissue /cell culture

The proposed project's goals are to understand the role of the MPS1 protein kinase in S. cerevisiae spindle pole body (SPB) duplication and in the spindle assembly checkpoint, and to determine if this kinase is widely conserved in the control of centrosome duplication. The formation of mitotic and meiotic spindles responsible for chromosome transmission is dependent upon proper centrosome duplication and function. Understanding centrosome duplication will be pertinent to dissecting the mechanisms of nondisjunction involved in chromosome imbalance and in the expression of recessive mutations in tumor- suppressing genes. Mutations in the MPS1 gene cause defects in SPB duplication and the spindle assembly checkpoint pathway. The investigator's are now able to monitor Mps1p (epitope-tagged) protein kinase activity isolated from yeast at endogenous levels. He will use this reagent to study how the kinase activity of Mps1p is regulated during the cell cycle. Mutagenesis to separate the two functions of Mps1p and the analysis of Mps1p phosphorylation will be performed with the goal of understanding how Mps1p executes its two roles during the cell cycle. To identify genes whose products interact with Mps1p, they plan to identify suppressors of the distinct dosage phenotypes of overexpressing either active or catalytically inactive MPS1. These will be analyzed to determine how they interact with MPS1 and to determine their role in SPB duplication or the spindle assembly checkpoint. The investigator's have identified mutations that are inviable in combination with mutations in the MPS1 gene. One he will continue to study is the novel, essential MOE1 gene that appears to be required for normal spindle function. They also will isolate the genes corresponding to several other synthetic lethal mutations they have identified. Molecular analysis of these newly identified genes should indicate how the encoded gene product interacts with Mps1p, and demonstrate if the new genes is involved in SPB duplication or the spindle checkpoint. Sequence homologues of MPS1 have been identified in various organisms. In mice a potential homologue is encoded by the esk gene. They propose to study the expression and activity of esk in mouse embryonic fibroblasts. He also will overexpress both active and inactive esk in mouse cells and determine if the cells exhibit phenotypes indicative of defects in centrosome duplication or the spindle assembly checkpoint. The results should indicate if the MPS1 kinase encodes a conserved function in either of its known roles.

拟议项目的目标是了解 MPS1 的作用 酿酒酵母纺锤体极体 (SPB) 复制中的蛋白激酶 在纺锤体装配检查点，并确定该激酶是否是 在中心体复制的控制中广泛保守。 这 负责染色体的有丝分裂和减数分裂纺锤体的形成 传输依赖于适当的中心体复制和 功能。 了解中心体复制将有助于 剖析涉及染色体的不分离机制 肿瘤中隐性突变的表达失衡 抑制基因。 MPS1 基因突变会导致 SPB 复制缺陷和 主轴装配检查点路径。 调查员现在能够 监测 Mps1p（表位标记）蛋白激酶活性 内源水平的酵母。 他将使用这种试剂来研究如何 Mps1p 的激酶活性在细胞周期中受到调节。 分离Mps1p两种功能的诱变及分析 进行 Mps1p 磷酸化的目的是为了了解 Mps1p 如何在细胞周期中执行其两个角色。 识别 他们计划识别其产物与 Mps1p 相互作用的基因 过表达的不同剂量表型的抑制因子 活性或催化非活性 MPS1。 这些将被分析为 确定它们如何与 MPS1 交互并确定它们在 SPB 中的角色 重复或主轴装配检查点。 研究人员已经确定了无法存活的突变 与 MPS1 基因突变相结合。 他将继续做的一件事 研究发现新的、必需的 MOE1 基因似乎是 主轴功能正常。 他们还将分离出相应的基因 他们已经发现了其他几种合成致死突变。 这些新发现的基因的分子分析应该表明如何 编码的基因产物与 Mps1p 相互作用，并证明如果 新基因参与 SPB 复制或纺锤体检查点。 MPS1 的序列同源物已在多种生物体中得到鉴定。 在小鼠中，esk 基因编码潜在的同源物。 他们提议 研究小鼠胚胎中esk的表达和活性 成纤维细胞。 他还会过度表达活跃和不活跃的 esk 小鼠细胞并确定细胞是否表现出指示的表型 中心体复制或纺锤体组装检查点的缺陷。 结果应表明 MPS1 激酶是否编码保守的 以其已知的角色发挥作用。