Regulation of Cytokinesis in Fission Yeast

裂殖酵母细胞分裂的调控

• 批准号: 7027062
• 负责人: DANNEL MCCOLLUM
• 金额: $ 30.12万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7027062
• 关键词: Schizosaccharomyces pombe; actins; alleles; biological signal transduction; cell cycle; cell cycle proteins; cell motility; cytogenetics; enzyme activity; enzyme substrate; fungal genetics; gene mutation; genetic regulation; immunoprecipitation; intermolecular interaction; mass spectrometry; molecular cloning; phosphorylation; protein kinase; tissue /cell culture; yeast two hybrid system

DESCRIPTION (provided by applicant): The long-term goal of this project is to understand how cytokinesis is regulated, and how cytokinesis is coordinated with other mitotic events such as spindle formation and chromosome segregation. To ensure proper segregation of genetic material, cell division must initiate at an appropriate time, and there must be some mechanism to delay cytokinesis if the chromosomes have not been properly segregated. Failure to do so could lead to abnormal chromosome segregation, anueploidy, and cancer. A large number of studies from many labs have shown that the basic mechanisms of cell cycle control are highly conserved between yeast and human cells. A conserved signaling network called the SIN in the fission yeast S. pombe functions to trigger initiation of cytokinesis at the end of anaphase. We have found that this network is crucial for coordinating cell and nuclear division to ensure that cells maintain genomic stability. Key components of the SIN include three-protein kinase called Cdc7p, Sidlp, and Sid2p. In the studies proposed here, we will elucidate the molecular mechanisms by which the SIN functions in coordinating late mitotic events. My specific aims are: (1) To characterize the precise molecular interactions between the Cdc7p, Sidlp, and Sid2p protein kinases required for signaling initiation of cytokinesis. (2) To define domains of Sid2p required for subcellular localization to the SPB, cell division site, and microtubules, to define domains of Sid2p required for interaction with Mob l p and Cdc 1 l p, to understand how Mob l p functions to promote Sid2p kinase activity, and to identify Sid2p-Mob l p interacting proteins by biochemical purification of Sid2p-Mob l p protein complexes. (3) To characterize the mechanism by which the sus1 mutation suppresses mutations in the SIN, to clone the sus1 + gene and to characterize the molecular interactions between Sus1p and the SIN. (4) To characterize the role of the Dma1p ubiquitin ligase in inhibiting the SIN and preventing cells from exiting mitosis and dividing if the mitotic spindle is defective, to determine if it is essential for the SIN to be inhibited to maintain the spindle checkpoint, to determine if Dma1p functions to inhibit C1p1p to maintain Cdc2p in a tyrosine dephosphorylated state in response to the spindle checkpoint, to identify components of the SIN that are inhibited by Dma1p, and to identify potential Dma1p targets and interacting proteins by biochemical purification of Dma1p protein complexes.

描述（由申请人提供）：该项目的长期目标是了解细胞因子的调节方式，以及如何与其他有丝分裂事件（例如纺锤体形成和染色体分离）协调细胞因子。为了确保遗传物质的适当分离，必须在适当的时间启动细胞分裂，如果染色体未正确隔离，则必须有一些机制延迟细胞因子。不这样做可能导致异常的染色体分离，厌氧和癌症。来自许多实验室的大量研究表明，细胞周期控制的基本机制在酵母菌和人类细胞之间高度保守。裂变酵母菌中称为sin的保守信号网络，pombe函数在后期结束时触发细胞因子的启动。我们发现该网络对于协调细胞和核分裂至关重要，以确保细胞保持基因组稳定性。罪的关键成分包括称为CDC7P，SIDLP和SID2P的三蛋白激酶。在此处提出的研究中，我们将阐明罪在协调晚期有丝分裂事件中起作用的分子机制。我的具体目的是：（1）表征CDC7P，SIDLP和SID2P蛋白激酶之间的精确分子相互作用，以信号启动细胞因子。 (2) To define domains of Sid2p required for subcellular localization to the SPB, cell division site, and microtubules, to define domains of Sid2p required for interaction with Mob l p and Cdc 1 l p, to understand how Mob l p functions to promote Sid2p kinase activity, and to identify Sid2p-Mob l p interacting proteins by biochemical purification of Sid2p-Mob l p protein复合物。 （3）表征SUS1突变抑制罪分突变的机制，以克隆SUS1 +基因并表征SUS1P与罪之间的分子相互作用。 （4）表征DMA1P泛素连接酶在抑制罪和防止细胞退出有丝分裂和分裂的细胞是否有丝分裂的作用，以确定是否要抑制罪过是否必须抑制sins spindle septlepoint，以确定DMA1P是否可以抑制C1p1p抑制CDC2P，以抑制CDC2P，以抑制CDCC2 P.主轴检查点，以识别DMA1P抑制的SIN的成分，并通过DMA1P蛋白质复合物的生化纯化来鉴定潜在的DMA1P靶标和相互作用的蛋白质。