Intra- & interspecies variation in oligosaccharide by MS

描述（由申请人提供）：低聚糖参与一系列细胞过程，包括识别、生长和粘附。它对人类健康的重要性涵盖了生殖、感染和癌症等多种领域。结构多样性和异质性是低聚糖令人难以置信的多功能性的原因，但这些特征使其难以进行分析。尽管如此，最近在质谱法的帮助下，在确定结构方面取得了重大进展。然而，结构解释仍然只是理解结构-功能关系的一步。低聚糖多样性的测定是下一个重要的步骤，但它代表着一个艰巨的挑战。它需要将结构解析、快速鉴定和表达水平定量相结合。本研究将测定非洲爪蟾卵细胞外基质中寡糖的多样性。非洲爪蟾（Xenopus laevis）卵是脊椎动物繁殖的重要模型。细胞外基质参与许多功能，包括保护和精子获能。它由受精卵层、卵黄包膜和三层蛋冻组成。这四层都是由糖蛋白组成的。果冻的糖基化程度很高，按重量计含有60%的聚糖。蛋鸡的生物学功能是已知的，但寡糖的具体作用是相对未知的。将开发表征低聚糖多样性的方法，为糖组学提供分析工具。这些方法将主要采用质谱法，并将用于快速阐明未知中性和阴离子组分的结构，鉴定已知组分，并定量其丰度。个体之间和单个鸡蛋之间的寡糖多样性将被确定。在此过程中，将开发单蛋低聚糖分析方法。个体之间的巨大多样性符合外生压力作为多样性驱动力的理论。然而，单个鸡蛋之间的低聚糖多样性很小。作为该项目的一部分，卵黄包膜或受精层将分析其低聚糖含量。卵黄膜类似于哺乳动物的透明带。本研究将为哺乳动物单个卵子的分析奠定基础。

DESCRIPTION (provided by applicant): Oligosaccharides are involved in a host of cellular processes including recognition, growth, and adhesion. Its importance to human health encompasses areas as diverse as reproduction, infection, and cancer. Structural diversity and heterogeneity is responsible for the incredible versatility of oligosaccharides, but these characteristics make it difficult to do analysis. Nonetheless, significant progress in determining structures has been made aided recently by mass spectrometry. Structural elucidation, however, is still only one-step in understanding structure-function relationship. The determination of oligosaccharide diversity is the next important step, but it represents a formidable challenge. It requires the combination of structural elucidation, rapid identification and the quantitation of expression levels. In this research the diversity of oligosaccharides in the extracellular matrix of the egg of Xenopus laevis will be determined. The egg of Xenopus laevis is an important model for vertebrate reproduction. The extracellular matrix is involved in a number of functions including protection and sperm capacitation. It consists of the fertilization layer, the vitelline envelope, and three layers of egg jelly. All four layers are composed of glycoproteins. The egg jelly is highly glycosylated with 60% glycans by weight. The biological functions of the layers are largely known but the specific roles of the oligosaccharides are relatively unknown. Methods for characterizing oligosaccharide diversity will be developed to provide analytical tools for glycomics. These methods will employ primarily mass spectrometry and will be used to rapidly elucidate structures of unknown neutral and anionic components, identify known components, and quantitate their abundances. The diversity of oligosaccharides between individuals and between individual eggs will be determined. In the process, methods for the oligosaccharide analysis of single eggs will be developed. Large diversity is expected between individuals to conform to the theory of exogenous pressures as the driving force for diversity. However, oligosaccharide diversity between individual eggs will be small. As part of this project, the vitelline envelope, or the fertilization layer, will be analyzed for its oligosaccharide content. The vitelline envelope is analogous to the zona pellucida in mammals. This research will lay the foundation for the analysis of single mammalian eggs.