Molecular Mechanisms of Meiotic Maturation in Drosophila

果蝇减数分裂成熟的分子机制

基本信息

批准号：
7887289
负责人：
Daniela Drummond-Barbosa
金额：
$ 32.8万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-05-01 至 2014-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7887289
关键词：
Accounting Address Affect Animal Model Binding Biochemical Cell Cycle Cell Cycle Proteins Cell Cycle Regulation Cell Division Process Cellular biology Chromosome Deletion Chromosome Segregation Complement Complex Congenital Abnormality Contraceptive Agents Coupled Cues Cyst Data Defect Development Drosophila genus Drosophila melanogaster Event Failure Female Fertilization in Vitro Figs - dietary Funding Genes Genetic Germ Cells Growth Haploidy Heterozygote Hormonal Human In Vitro Infertility Knowledge Lead Meiosis Meiotic Prophase I Metaphase Methodology Molecular Molecular Genetics Molecular Mechanisms of Action Mus Mutation Oocytes Organism Ovarian Ovulation Pattern Phenotype Process Prophase Proteins Research Role Spontaneous abortion Sterility System Testing Time Ubiquitin Specific Protease 8 Ubiquitination Woman Work Yeasts anaphase-promoting complex base blastomere structure endosulfine expression cloning in vivo mutant oocyte maturation protein function public health relevance tool ubiquitin-protein ligase yeast two hybrid system

项目摘要

DESCRIPTION (provided by applicant): Meiosis is a fundamental process that is coupled to gamete development. Oocytes arrest in prophase of the first meiotic division to allow for growth. Release from prophase I occurs during meiotic maturation, but the molecular mechanisms regulating this process are incompletely understood. Meiotic maturation defects can result in infertility or in inaccurate segregation of chromosomes, leading to miscarriages and/or birth defects. The fruitfly Drosophila melanogaster offers sophisticated genetic and molecular tools, and a well described ovarian cell biology, making it a powerful system to investigate the control of meiotic maturation. Drosophila oocytes enter meiosis shortly after germline cyst formation and arrest in prophase I during most of their development. After meiotic maturation, oocytes arrest again in metaphase I until ovulation. In the prior funding period, we demonstrated that 1-Endosulfine (Endos) is required for meiotic maturation. Our data suggest that Endos promotes the stability of the cell cycle regulators CyclinA, Polo and Twine/Cdc25 (all known to be targets of the Anaphase Promoting Complex, or APC), and that it also has a separate role via inhibition of the E3 ubiquitin ligase Elgi to promote meiotic maturation. Expression of ENSA, the human 1- endosulfine, rescues the endos meiotic defect, and 1-endosulfine is expressed in mouse oocytes, suggesting conservation of the meiotic function of 1-endosulfine. Our overarching hypothesis is that Endos is a central regulator of meiotic maturation via two mechanisms: it inhibits the activity of the APC to allow the accumulation of key cell cycle regulators, and it antagonizes the ubiquitination of Elgi targets. We will test this hypothesis through the following specific aims: 1) to determine if Endos is a negative regulator of the APC; 2) to determine how the E3 ubiquitin ligase Elgi regulates meiotic maturation downstream of Endos; and 3) to elucidate the molecular mechanism of action of Endos. Elucidation of the molecular mechanisms of meiotic maturation could potentially lead to therapies to address this cause of infertility, as well as to new contraceptives. Furthermore, this knowledge could also lead to technological strategies for in vitro maturation of human oocytes to complement current in vitro fertilization methodology. PUBLIC HEALTH RELEVANCE: Failure of the oocyte to undergo meiotic maturation leads to infertility. Our prior work has identified Endos as a major regulator of meiotic maturation, and we propose to use powerful research tools in fruitflies to understand the function of this protein. Our studies could potentially lead to additional therapies to address infertility, as well as to technological strategies to complement current in vitro fertilization methodology.

描述（由申请人提供）：减数分裂是一个与配子开发相结合的基本过程。卵母细胞在第一个减数分裂划分的预言中逮捕，以允许生长。从预言中释放在减数分裂成熟期间发生，但是调节该过程的分子机制是不完全理解的。减数分裂的成熟缺陷可能导致染色体的不育或不准确隔离，导致流产和/或出生缺陷。果蝇果蝇Melanogaster提供了复杂的遗传和分子工具，以及描述的卵巢细胞生物学，使其成为研究减数分裂成熟的强大系统。果蝇卵母细胞在生殖线囊肿形成后不久进入减数分裂，并在大部分发育过程中在预言I中停止。减数分裂成熟后，卵母细胞再次在中期I中逮捕直至排卵。在以前的资金期间，我们证明了减数分裂成熟需要1-硫硫胺（endos）。我们的数据表明，ENDOS促进了细胞周期调节剂Cyclina，Polo和Twine/CDC25（所有已知都是促进复合物或APC的靶标）的稳定性，并且它也通过抑制E3泛素蛋白 - 酶Elgi来抑制以促进减数分裂成熟。 ENSA的表达，人类1-内硫碱，挽救了减数分裂缺陷，1-硫丁硫酸盐在小鼠卵母细胞中表达，这表明保存了1-琼脂的减数分裂功能。我们的总体假设是，通过两种机制，Endos是减数分裂成熟的中心调节剂：它抑制APC的活性，从而允许关键细胞周期调节剂的积累，并拮抗ELGI靶标的泛素化。我们将通过以下特定目的检验这一假设：1）确定endos是否是APC的负调节剂； 2）确定E3泛素连接酶Elgi如何调节胚胎下游的减数分裂成熟； 3）阐明了内质作用的分子机理。阐明减数分裂成熟的分子机制可能会导致疗法解决这种不育原因以及新的避孕药。此外，这种知识还可能导致人类卵母细胞体外成熟以补充当前体外受精方法的技术策略。公共卫生相关性：卵母细胞无法进行减数分裂成熟会导致不育。我们先前的工作已将恩托斯（Endos）确定为减数分裂成熟的主要调节剂，我们建议在水果粉中使用强大的研究工具来了解该蛋白质的功能。我们的研究可能会导致其他疗法来解决不孕症，以及补充当前体外受精方法的技术策略。