RNA Localization in Xenopus Oocytes

项目摘要 细胞质rna定位是产生胚胎和体细胞的一种广泛的机制。 两极。在脊椎动物中，Vg1 mRNAs是一个定位的mRNAs的突出例子，它在 胚胎图案。VG1mRNA编码一种多肽生长因子，在卵子发生过程中定位于 非洲爪哇卵母细胞的营养细胞质。Vg1蛋白在小鼠植物半球的限制性表达 卵子对胚胎的正确构型至关重要，使Vg1 mRNA的定位成为 了解母体分子如何局部化以影响模式和极性。 这项研究项目的目标是研究RNA分子是如何针对特定区域的 细胞质通过空间受限的蛋白质表达来产生细胞极性。的基础 我们对支配这一过程的分子相互作用的研究进展奠定了这一研究的基础。 我们的实验定义了关键的RNA-蛋白质和蛋白质-蛋白质相互作用，导致组装 具有运输能力的RNP复合体，并在定位途径中发现了不同的步骤。我们目前的情况 提案试图通过研究这些步骤之间的动态转换来扩展这些发现 定位途径。我们将使用体内和体外相结合的方法来确定分子 Vg1基因局部表达的机制。提出了三个具体目标：在目标I中， 我们将表征细胞质Vg1 RNP复合体的动力学和运输，在Aim II中，我们将 分析RNP转运颗粒的组装和活性，并在目标III中探讨其作用机制 将翻译抑制和RNA定位结合在一起 这项拟议的研究旨在揭示信使核糖核酸分子的运输机制。 在细胞内产生空间受限的蛋白质表达，并将提供对如何发育的洞察 信号在脊椎动物胚胎中的空间分布。这项工作将影响与人类健康相关的问题 例如出生缺陷，以及与RNA运输缺陷和 局部蛋白质合成。

Project Summary Cytoplasmic RNA localization is a widespread mechanism for generating both embryonic and somatic cell polarity. Among vertebrates, Vg1 mRNA is a prominent example of a localized mRNA that plays a role in embryonic patterning. Vg1 mRNA encodes a peptide growth factor, and is localized during oogenesis to the vegetal cytoplasm of Xenopus oocytes. Restricted expression of Vg1 protein in the vegetal hemisphere of the egg is critical for correct patterning of the embryo, making localization of Vg1 mRNA an important model for understanding how maternal molecules are localized to influence pattern and polarity. The goal of this research project is to investigate how RNA molecules can be targeted to specific regions of the cell cytoplasm to generate cell polarity through spatially restricted protein expression. The foundation for this investigation has been laid by our progress studying the molecular interactions that govern this process. Our experiments have defined critical RNA-protein and protein-protein interactions leading to assembly of a transport-competent RNP complex and have uncovered distinct steps in the localization pathway. Our current proposal seeks to extend these findings by studying the dynamic transitions between these steps in the localization pathway. We will use a combination of in vivo and in vitro approaches to determine the molecular mechanisms responsible for localized expression of Vg1 mRNA. Three specific aims are proposed: In Aim I, we will characterize the dynamics and transport of the cytoplasmic Vg1 RNP complex, in Aim II, we will analyze the assembly and activity of RNP transport granules and in Aim III we will investigate the mechanisms that couple translational repression and RNA localization The proposed research is designed to reveal the mechanisms by which mRNA molecules are transported within cells to generate spatially restricted protein expression, and will provide insight into how developmental signals are spatially distributed in the vertebrate embryo. This work will impact issues related to human health such as birth defects, as well as neurological diseases that have been linked to defective RNA transport and localized protein synthesis.