Investigate the Molecular Basis that Controls the Timing of Spindle Elongation

研究控制纺锤体伸长时间的分子基础

基本信息

批准号：
8083720
负责人：
Yanchang Wang
金额：
$ 28.09万
依托单位：
FLORIDA STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-15 至 2015-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8083720
关键词：
Anaphase Binding Proteins Biochemical Genetics Biomedical Research Cell Cycle Cell Nucleolus Cells Characteristics Chromosome Segregation Chromosomes Congenital Abnormality Cyclin A Cyclin-Dependent Kinases Cyclins Data Defect Ensure Equilibrium Exhibits Hereditary Disease Investigation Kinetics Knowledge Lead Malignant Neoplasms Mammals Mitosis Mitotic Mitotic Activity Molecular Morphology Outcome Pathway interactions Phosphoric Monoester Hydrolases Phosphorylation Play Plus End of the Microtubule Protein Dephosphorylation Regulation Research Role S Phase Saccharomycetales Students Substrate Specificity Temperature Testing Time Time Study Training Work base cancer cell cancer diagnosis cancer therapy daughter cell expectation human PLK1 protein innovation mutant overexpression premature prevent segregation spindle pole body tumor progression

项目摘要

DESCRIPTION (provided by applicant): Chromosome mis-segregation is a common cause of genetic disorders, including birth defects and cancer. Spindle elongation is essential for chromosome segregation and premature spindle elongation leads to abnormal chromosome segregation. Thus, the timing of spindle elongation must be rightly regulated. The objective of this application is to determine how cells ensure that spindle elongation occurs at the right time. The central hypothesis of the application is that, in budding yeast, the balance of mitotic CDK (cyclin dependent kinase) vs. S-phase CDK controls the timing of spindle elongation. S- phase CDK plays a negative role in spindle elongation by phosphorylating the S-phase CDK-specific substrates, whereas mitotic CDK promotes spindle elongation by indirectly stimulating the dephosphorylation of S-phase CDK substrates. The Cdc14 phosphatase is responsible for the dephosphorylation of S-phase CDK substrates and mitotic CDK allows this to happen by activating the FEAR (Cdc Fourteen Early Anaphase Release), a mitotic exit pathway that frees Cdc14 from the nucleolus during early anaphase. We further propose that S-phase CDK inhibits spindle elongation through the phosphorylation of Spc110, a component of the spindle pole body (SPB). We will take a comprehensive biochemical, genetic, and functional approach to study the timing control of spindle elongation in budding yeast. The objective of the application will be accomplished by pursuing three specific aims. 1) Test the hypothesis that S-phase and mitotic CDKs antagonistically regulate spindle elongation. 2) Test the hypothesis that mitotic CDK activates the FEAR pathway to counteract the negative effect of S-phase CDK on spindle elongation. 3) We hypothesize that S-phase CDK inhibits spindle elongation by phosphorylating Spc110, a component of the spindle pole body. The proposed work is innovative because it will reveal the molecular basis that controls the timing of spindle elongation. It is our expectation that the tightly regulated activities of mitotic and S-phase CDK during cell cycle ensure the correct timing of spindle elongation. Such outcomes will be significant because new knowledge will suggest new targets for preventing genetic disorders, such as cancer. Moreover, the support of this R15 proposal will enable the training of undergraduate students and expose them to biomedical research. PUBLIC HEALTH RELEVANCE: During mitosis, spindle elongation segregates duplicated chromosomes into two daughter cells. Premature spindle elongation leads to abnormal chromosome segregation, a characteristic of many cancer cells. This proposal aims to understand the molecular basis that controls the timing of spindle elongation. Therefore, this research will potentially uncover new targets for cancer diagnosis and treatment. Moreover, many undergraduate students will receive training in biomedical research by working on this project.

描述（由申请人提供）：染色体错误分离是遗传性疾病的常见原因，包括出生缺陷和癌症。纺锤体伸长对于染色体分离至关重要，纺锤体过早伸长会导致染色体分离异常。因此，必须正确调节纺锤体伸长的时间。该应用的目的是确定细胞如何确保纺锤体在正确的时间发生伸长。该应用的中心假设是，在芽殖酵母中，有丝分裂 CDK（细胞周期蛋白依赖性激酶）与 S 期 CDK 的平衡控制着纺锤体伸长的时间。 S期CDK通过磷酸化S期CDK特异性底物而在纺锤体伸长中发挥负面作用，而有丝分裂CDK通过间接刺激S期CDK底物的去磷酸化来促进纺锤体伸长。 Cdc14 磷酸酶负责 S 期 CDK 底物的去磷酸化，有丝分裂 CDK 通过激活 FEAR（Cdc 14 早期后期释放）来实现这一过程，FEAR 是一种有丝分裂退出途径，可在后期早期将 Cdc14 从核仁中释放出来。我们进一步提出，S 期 CDK 通过纺锤体极体 (SPB) 的组成部分 Spc110 的磷酸化来抑制纺锤体伸长。我们将采用综合的生化、遗传和功能方法来研究芽殖酵母纺锤体伸长的时间控制。该应用程序的目标将通过追求三个具体目标来实现。 1) 检验 S 期和有丝分裂 CDK 拮抗调节纺锤体伸长的假设。 2) 检验有丝分裂CDK激活FEAR通路以抵消S期CDK对纺锤体伸长的负面影响的假设。 3）我们假设S期CDK通过磷酸化纺锤体极体的组成部分Spc110来抑制纺锤体伸长。这项工作具有创新性，因为它将揭示控制纺锤体伸长时间的分子基础。我们期望细胞周期期间有丝分裂和S期CDK的严格调节活性确保纺锤体伸长的正确时机。这样的结果将意义重大，因为新知识将提出预防癌症等遗传性疾病的新目标。此外，对 R15 提案的支持将有助于本科生的培训，并使他们接触生物医学研究。公共卫生相关性：在有丝分裂期间，纺锤体伸长将重复的染色体分离成两个子细胞。纺锤体过早伸长导致染色体分离异常，这是许多癌细胞的特征。该提案旨在了解控制纺锤体伸长时间的分子基础。因此，这项研究将有可能发现癌症诊断和治疗的新靶点。此外，许多本科生将通过参与该项目接受生物医学研究的培训。