CONTROL OF THE EXIT FROM MITOSIS IN FISSION YEAST

裂殖酵母有丝分裂退出的控制

• 批准号: 6385801
• 负责人: SHELLEY SAZER
• 金额: $ 27.95万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-05-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6385801
• 关键词: Schizosaccharomyces pombe; biological signal transduction; cell cycle; enzyme activity; fungal genetics; gene complementation; gene expression; gene interaction; guanosinetriphosphatases; immunoelectron microscopy; laboratory rabbit; molecular cloning; phenotype; protein structure function; southern blotting; temperature sensitive mutant; western blottings

The long term objective of the proposed research is to elucidate the mechanism by which the morphological changes required for the mitosis to interphase transition are regulated. Because of its excellent genetics and cytology, fission yeast is an excellent experimental system in which to study this point in the cell cycle at which the chromosomes decondense, the nuclear envelope reforms around the chromosomes, and the cells undergo cytokinesis and separate from one another. The focus of this proposal is on spi1, the evolutionarily conserved GTPase that is essential for the mitosis to interphase transition in fission yeast. spi1 is nearly identical to the human proto-oncogene p21ras in its GTP binding and hydrolysis domains, and its regulators are also evolutionarily conserved. The proposed studies will further our understanding of the function of this eukaryotic GTPase in particular, and the findings will be applicable to studies of the large family of structurally related GTPases that regulate a wide variety of cellular functions, and to the elucidation of the mechanism by which GTPases interact with their downstream targets via the activation of signal transduction pathways. Perturbations in the GTPase cycle, leading to an accumulation of either the GTP- or GDP-bound forms, have similar, easily monitored phenotypic consequences. This observation led to the generation of a collection of genes and mutants that based on a variety of criteria are likely to identify regulators and downstream targets of the spi1 GTPase. The proposed genetic, phenotypic, and biochemical analyses will elucidate their relationship to the known components of the spi1 GTPase system. The Specific Aims of this proposal are: SPECIFIC AIM I. Identify targets of the spi1 GTPase by characterizing the sns mutants and the med genes that interact genetically with components of the GTPase system; SPECIFIC AIM II. Identify targets of the spi1 GTPase by isolating genes that when overproduced can rescue the temperature sensitive lethality of the pim1-d1 mutuant; and SPEICIFIC AIM III. Test the hypothesis that the nuclear envelope is a downstream target of the spi1 GTPase system.

拟议研究的长期目标是阐明 有丝分裂所需的形态变化的机制 到相间转变的调节。 由于其优良的 在遗传学和细胞学方面，裂殖酵母是一个很好的实验系统， 来研究细胞周期中的这一点， 当细胞核被膜在染色体周围重新形成时， 细胞经历胞质分裂并彼此分离。 的焦点 这个提议是关于spi 1的，spi 1是进化上保守的GT3， 在分裂酵母中有丝分裂到间期转变所必需的。 spi 1与人原癌基因p21 ras的GTP几乎相同 结合和水解结构域，其调节剂也 进化上保守。 建议的研究将进一步促进我们的 特别是对真核生物GT3功能的理解， 这些发现将适用于大家庭的研究， 结构上相关的GTP酶，其调节多种细胞 功能，并阐明GTP酶的机制， 通过激活信号与下游靶分子相互作用 转导途径。在GTTT周期的扰动，导致一个 GTP或GDP结合形式的积累，具有类似的，容易 监测表型结果。 这一观察导致了 一系列基因和突变体的产生， 标准可能会确定监管机构和下游目标， spi1 GTtlets。 建议的遗传，表型，和生化 分析将阐明它们与已知组分的关系， spi 1 GTdem系统。本提案的具体目标是： AIM岛 通过表征sns来识别spi 1 GTcnt的靶标 突变体和与基因相互作用的基因， GTALK系统;特定目标II.确定spi 1 GTdR的靶点 通过分离基因，当过度生产时， pim 1-d1突变体的敏感致死性;和SPEICIFIC AIM III。测试 假设核被膜是一个下游的目标， spi 1 GT3系统。