Drosophila as a model to dissect the rise and role of calcium in egg activation.

果蝇作为模型来剖析钙在卵子激活中的上升和作用。

• 批准号: 9323477
• 负责人: Mariana Federica Wolfner
• 金额: $ 19.15万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-29 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9323477
• 关键词: Affect; Assisted Reproductive Technology; Biological Models; Calcineurin; Calcium; Candidate Disease Gene; Cell Differentiation process; Cell Nucleus; Centrioles; Coupled; Cytoplasm; Data; Development; Diagnosis; Disease; Drosophila genus; Embryo; Embryonic Development; Environment; Event; Family; Fertilization; Future; Genetic Screening; Genetic Transcription; Genome; Germ Cells; Goals; Haploidy; Hour; Human; Infertility; Insecta; Ion Channel; Mammals; Maternal Messenger RNA; Measures; Mediating; Meiosis; Methods; Modeling; Modification; Oocytes; Organelles; Organism; Orthologous Gene; Phase; Phosphorylation; Process; Proteins; Proteome; Role; Sea Urchins; Signal Transduction; Site; Stem cells; TRP channel; Testing; Totipotent; Transducers; Translations; Vertebrates; Work; base; calcineurin phosphatase; egg; fly; genetic manipulation; inhibitor/antagonist; male; mechanical pressure; pressure; receptor; sperm cell; transcriptome; zygote

Project Summary A differentiated, mature oocyte is “activated” to become totipotent and to begin embryo development through an increase in its cytoplasmic free Ca2+ levels. In mammals, this increase is initially induced by the fertilizing sperm, which stimulates release of Ca2+ from internal stores. However, recent studies have shown that subsequent Ca2+ oscillations that are essential for mammalian egg activation require influx of external Ca2+ from the environment into the oocyte, through as yet unknown channels and mechanisms. Although Drosophila had not been considered a good model for these processes because its eggs activate prior to fertilization, our recent work has shown that Drosophila egg activation also involves a local Ca2+ influx. This influx is followed by a wave of increased Ca2+ that sweeps through the egg cytoplasm, using mechanisms like those used by mammalian oocytes. We showed that the initial Ca2+ influx in Drosophila occurs at the oocyte poles, through mechanosensitive channels – most likely conserved channels in the TRP family. We propose to establish Drosophila as a new model for the Ca2+-based phase of egg activation. We will use this model to identify the channels that mediate sperm-independent Ca2+ influx and the conditions that cause Ca2+ channels to be open only at the egg poles. We will also determine whether the increased Ca2+ mediates the changes to the oocyte phosphoproteome that normally accompany egg activation, and whether the Ca2+ signal transducer calcineurin is required for these phosphoproteome changes. We expect the results of our studies to be generalizable to mechanisms in mammalian egg activation. Moreover, conserved proteins with Ca2+- dependent phosphomodifications will be candidates for future testing as markers for assessing human ART conditions, oocyte quality and aiding the diagnosis of infertilities that cannot respond to current ART methods.

项目摘要 差异化的成熟卵母细胞被“激活”以变成全能并开始胚胎 通过增加其细胞质游离Ca2+水平的发展。在哺乳动物中，这个 最初，受精的精子诱导了增加，这刺激了从中释放Ca2+ 内部商店。但是，最近的研究表明，随后的CA2+振荡 对于哺乳动物卵的激活至关重要的是外部Ca2+从 环境进入卵母细胞，通过未知的渠道和机制。 尽管果蝇没有被认为是这些过程的好模型 因为它的卵在受精前激活，所以我们最近的工作表明果蝇 鸡蛋激活还涉及局部Ca2+影响。这种影响之后是一波 使用像这样的机制增加了通过鸡蛋细胞质的糖果的Ca2+ 由哺乳动物卵母细胞使用。我们表明果蝇中的最初Ca2+影响发生 通过机械敏感通道，在卵母细胞杆上 - 最有可能保守 TRP家族中的频道。我们建议建立果蝇作为新模型 基于Ca2+的卵激活期。我们将使用此模型来确定 介导非精子无关的C​​a2+影响以及导致Ca2+通道的条件 仅在鸡蛋杆上打开。我们还将确定增加的Ca2+是否增加 介导通常容纳卵的卵母细胞磷酸蛋白酶的变化 激活以及是否需要Ca2+信号传感器钙调神经酶 磷酸蛋白酶变化。我们希望我们的研究结果可以推广到 哺乳动物卵激活的机制。此外，构成具有Ca2+ - 的蛋白质 依赖的磷酸化将是未来测试作为标记的候选者 评估人类艺术条件，卵母细胞质量和帮助的诊断 这无法响应当前的艺术方法。