Oligosaccharides Regulating Cell Function

描述(申请人提供)：细胞凋亡是一个高度调控的细胞死亡过程。细胞凋亡在分子水平上的失控与包括癌症在内的多种人类疾病有关。低分子量果胶(LMP)是一种来源于植物细胞壁的复杂碳水化合物，已被证明可诱导癌细胞凋亡，导致小鼠肿瘤体积缩小。然而，由于LMP的复杂结构和样本异质性，解释这种观察到的细胞凋亡的机制的结构-功能关系仍然难以捉摸。因此，通过将酶和灵敏的分析技术与为表征肝素/硫酸乙酰肝素类糖胺而开发的生物检测相结合的策略进行扩展。 在这项拨款申请中提出的实验旨在生产更明确、更具生物活性的LMP-衍生物。这些LMP寡糖将有助于阐明LMP的特定结构，这些结构负责多糖诱导细胞凋亡的作用。在我们初步实验结果的基础上，这项赠款申请的具体目标有两个：具体目标我将专注于扩大我们实验室开发的表征糖胺聚糖的方法，开发降解LMP和筛选反应产物所需的必要的酶和分析工具。第二个特定目标将在第一个特定目标中开发的酶和分析工具整合到一个系统的方案中，用于产生和纯化保留诱导细胞凋亡能力的已定义的LMP衍生物。总体而言，这项拨款申请中概述的研究将产生低分子量和结构异质性较低的LMP衍生低聚糖，这些低聚糖是进一步表征诱导细胞凋亡的细胞机制所必需的。这项赠款申请代表了一项高风险/高回报的承诺，旨在开发LMP作为治疗癌症的有效方法，以治疗因放松对细胞凋亡的管制而导致的衰弱疾病，如癌症。

DESCRIPTION (provided by applicant): Apoptosis is a highly regulated process of cell death. De-regulation of apoptosis at the molecular level has been implicated in a variety of human diseases, including cancer. Low molecular weight pectin (LMP), a complex carbohydrate derived from the wall of plant cells, has been shown to induce apoptosis in cancer cells leading to a reduction in tumor volume in mice. However, due to the complex structure and sample heterogeneity of LMP, a structure-function relationship to explain the mechanism underlying this observed apoptosis has remained elusive. Therefore, by extending the strategy of combining enzymes and sensitive analytical techniques with biological assays developed for the characterization of heparin/heparan sulfate-like glycosamino- glycans, the experiments proposed in this grant application are designed to produce more defined, biologically active LMP-derivatives. These LMP oligosaccharides will help provide clarity on the specific structure of LMP responsible for the polysaccharide's apoptosis-inducing effect. Building on the results of our initial experiments, the specific aims of this grant application are twofold: Specific Aim I will focus on expanding the methodology developed by our laboratory for the characterization glycosaminoglycans by developing the necessary enzymatic and analytical tools required for the degradation of LMP and the screening of the reaction products. Specific Aim II integrates the enzymatic and analytical tools developed in the first specific aim into a systematic protocol for the generation and purification of defined LMP derivatives that retain the ability to induce apoptosis in cells. As a whole, the research outlined in this grant application will yield LMP-derived oligosaccharides with lower molecular weight and less structural heterogeneity that are required for the further characterization of the cellular mechanism of action responsible for the induction of apoptosis. This grant application represents a high risk/high reward undertaking aimed at developing LMP as an effective treatment for of debilitating diseases caused by the deregulation of apoptosis, such as cancer.