Drosophila Genes Affecting Chromosome Segregation

影响染色体分离的果蝇基因

• 批准号: 7389489
• 负责人: MICHAEL L GOLDBERG
• 金额: $ 42.09万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-30 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7389489
• 关键词: Affect; Aging; Anaphase; Antibodies; Area; Behavior; Binding; Biochemical; Biochemical Pathway; Cell Cycle Progression; Cell division; Cells; Chromosome Condensation; Chromosome Segregation; Chromosomes; Cloning; Competence; Complex; Defect; Development; Down Syndrome; Drosophila genus; Drosophila melanogaster; Dynein ATPase; Ensure; Eukaryota; Eukaryotic Cell; Funding; Genes; Genetic Screening; Human; Individual; Insecta; Kinetochores; Laboratories; Lead; Malignant Neoplasms; Meiosis; Microscopy; Microtubules; Mitosis; Mitotic; Molecular Motors; Motor; Mutation; Oocytes; Operative Surgical Procedures; Organism; Pathway interactions; Phenotype; Phosphorylation; Phosphotransferases; Process; Prophase; Protein Kinase; Proteins; Purpose; Research; Research Personnel; Role; Role playing therapy; Side; Sister Chromatid; Site; Spontaneous abortion; Structure; Techniques; Testing; Time; Vertebrates; Xenopus; Xenopus oocyte; design; follow-up; insight; interest; mutant; neuroblast; novel; oocyte maturation; prevent; programs; research study; retinal rods; upstream kinase

DESCRIPTION (provided by applicant): Mistakes in chromosome segregation during meiosis or mitosis can lead to spontaneous abortion or to abnormalities such as Down syndrome. They have also been implicated in the processes leading to cancer and aging. Our laboratory has undertaken large-scale genetic screens using the organism Drosophila melanogaster to identify genes encoding proteins critical for ensuring proper chromosome segregation. In the first specific aim, we will investigate several novel components of the chromosomal kinetochores that were first found in our screens and that have been conserved among metazoans including humans. One area of focus in this aim is a multisubunit complex including the proteins ZW10, Rod, and Zwilch. This complex targets the molecular motor dynein to the kinetochore, and it is required in a currently unknown fashion for the operation of the spindle assembly checkpoint that regulates anaphase onset. We propose experiments to dissect the structure of this complex and to investigate its interactions with NudE, a dynein-associated protein whose role is currently not well understood. A second area of focus in this aim will explore the possibility that two new proteins identified in our genetic screens may together constitute a new subassembly at the kinetochore also needed for proper chromosome segregation. The second specific aim describes a new area of research for our laboratory. Mutations in greatwall, one of the Drosophila genes found in our screens, cause chromosome undercondensation because of delayed transit through prophase. The greatwall gene encodes a novel protein kinase with an unusual structure that is conserved in insects and vertebrates. We made antibody against the Xenopus Greatwall protein and used it to. deplete this kinase from oocyte extracts. To our surprise, Greatwall depletion prevented the extracts from entering or maintaining M phase. In the second specific aim, we will follow up these intriguing observations in order to understand Greatwall's role in mitotic progression. We propose experiments to define Greatwall's substrates as well as the upstream kinases involved in Greatwall activation during mitosis. Additional experiments will investigate Greatwall's possible developmental role in oocyte maturation and will search for other proteins with which this kinase associates. The proposed studies on Greatwall have the potential to offer unique mechanistic insights concerning mitotic entry in vertebrate cells.

描述（由申请人提供）：减数分裂或有丝分裂过程中染色体分离的错误可能导致自然流产或唐氏综合症等异常。它们还与导致癌症和衰老的过程有关。我们的实验室利用黑腹果蝇生物体进行了大规模的遗传筛选，以确定编码对于确保正确的染色体分离至关重要的蛋白质的基因。在第一个具体目标中，我们将研究染色体动粒的几种新成分，这些成分首先在我们的屏幕中发现，并且在包括人类在内的后生动物中保守。这一目标的一个重点领域是包括蛋白质 ZW10、Rod 和 Zwilch 的多亚基复合物。该复合物将分子运动动力蛋白靶向着丝粒，并且以目前未知的方式需要它来调节后期开始的纺锤体组装检查点的操作。我们提出实验来剖析该复合物的结构并研究其与 NudE 的相互作用，NudE 是一种动力蛋白相关蛋白，其作用目前尚不清楚。该目标的第二个重点领域将探索在我们的遗传筛选中鉴定的两种新蛋白质可能共同构成着丝粒处的新亚装配的可能性，这也是正确染色体分离所必需的。 第二个具体目标描述了我们实验室的新研究领域。 Greatwall 是我们在筛选中发现的果蝇基因之一，它的突变会由于前期转运延迟而导致染色体浓缩不足。长城基因编码一种新型蛋白激酶，具有在昆虫和脊椎动物中保守的不寻常结构。我们制作了针对非洲爪蟾长城蛋白的抗体并使用它。从卵母细胞提取物中耗尽该激酶。令我们惊讶的是，Greatwall 耗尽阻止了提取物进入或维持 M 相。在第二个具体目标中，我们将跟踪这些有趣的观察结果，以了解长城在有丝分裂进展中的作用。我们提出实验来定义 Greatwall 的底物以及有丝分裂期间参与 Greatwall 激活的上游激酶。其他实验将研究 Greatwall 在卵母细胞成熟中可能的发育作用，并将寻找与该激酶相关的其他蛋白质。拟议的长城研究有可能提供有关脊椎动物细胞有丝分裂进入的独特机制见解。