Novel insights from a divergent form of germ plasm

核糖核蛋白（Ribonucleoproteins，RNP）是许多生物学过程和细胞中的重要组成部分 类型黑腹果蝇的极粒长期以来一直是 了解RNP功能的系统。极性颗粒很小， 在果蝇中指定原始生殖细胞的异质RNP。在本提案中，我们 将利用我们的黄蜂模型系统Nasonia， 丽翅凤蝶纳苏尼亚相当于极性颗粒， 球形固体RNP称为卵小体。这与极性颗粒相反， 以许多小颗粒的形式存在于胚胎的后极。的 Nasonia卵小体在胚胎的后半部分经历了戏剧性的迁移， 这一过程在果蝇中没有对应的过程。最后，将卵小体挤出， 一个非常大的芽将分裂并产生极细胞。这是在强 与果蝇中的极细胞形成相反，极细胞形成是由细胞核迁移到 后皮层，在那里单个细胞由单个的小芽形成。的目标 这个建议是为了了解卵小体的分子和机械特性 这是其形态和功能与极地差异的基础 颗粒。我们将描述卵体的蛋白质组成，详细说明如何 翻译在卵小体中受到调节，并揭示了mRNA和蛋白质是如何在卵小体中表达的。 分布在卵小体中。然后我们将确定蛋白质之间的相互作用 这可能对卵小体的独特结构和功能很重要。最后我们 将采取深入的方法来表征新组件的功能， oosome。在这个项目结束时，我们将有一个机械的理解， 卵小体的组成和组成分子之间的相互作用 产生了一种新型的RNP。

Ribonucleoproteins (RNPs) are crucial elements in many biological processes and cell types. The polar granules of Drosophila melanogaster have long served as a model system for understanding the functions of RNPs. Polar granules are small, heterogeneous RNPs that specify the primordial germ cells in the fly. In this proposal, we will build upon the Drosophila knowledge using our wasp model system Nasonia vitripennis. The Nasonia equivalent of the polar granules is in the form of a large, spherical, solid RNP called the oosome. This is in contrast to the polar granules, which take the form of many small particles localized to the posterior pole of the embryo. The Nasonia oosome undergoes a dramatic migration within the posterior half of the embryo, a process which has not counterpart in Drosophila. Finally, the oosome is extruded in one very large bud that will divide and give rise to the pole cells. This is in strong contrast to pole cell formation in Drosophila, which is driven by the migration of nuclei to the posterior cortex, where individual cells form from small buds individually. The goal of this proposal is to understand the molecular and mechanistic properties of the oosome that are the basis for its morphological and functional differences from the polar granules. We will characterize the protein composition of the oosome, detail how translation is regulated within the oosome, and reveal how mRNAs and proteins are distributed throughout the oosome. We will then identify the interactions among proteins that may be important for the unique structure and function of the oosome. Finally, we will take in depth approaches to characterize the functions of novel components of the oosome. At the conclusion of this project, we will have a mechanistic understanding how the composition of the oosome and the interactions among the component molecules give rise to a novel form of RNP.