Isolation of a Receptor for a Fungal Wall Derived Elicitor of Phytoalexins

真菌壁衍生的植物抗毒素激发子受体的分离

• 批准号: 8904574
• 负责人: Michael Hahn
• 金额: $ 25.15万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-08-15 至 1993-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8904574&HistoricalAwards=false
• 关键词: Isolation; Receptor; Fungal; Wall; Derived

The objective of this research is to isolate and characterize the receptor for a biologically active hepta-B-glucoside. A radiolabeled hepta-B-glucoside elicitor, for use in ligand- binding studies, will be prepared by conjugation of the oligosaccharide to tyramine, followed by iodination of the conjugate. It has been established that a model heptaglucoside, maltoheptaose, can be conjugated to tyramine and furthermore, that the structural modifications of the hepta-B-glucoside elicitor required for radiolabeling with iodine are unlikely to affect its elicitor activity. A photoaffinity labeling reagent for receptor localization and identification studies will also be prepared. The receptor(s) for the hepta-B-glucoside elicitor will be identified and localized using standard cell fractionation techniques, ligand-binding assays, and photo-affinity labeling. If an elicitor receptor is identified, it will be purified and characterized. The proposed experiments will lay the groundwork for future studies to determine the physiological significance of the receptor(s) and to identify the role the receptor(s) play in the signal pathway that results in altered gene expression leading, in turn, to phytoalexin accumulation in affected plant cells.%%% Fungal-derived B-glucans, of the type from which the active hepta-B-glucoside was isolated, are active as inducers or enhancers of a variety of defense mechanisms in plants. The only biologically active B-glucan-derived fragment that has been purified to homogeneity and structurally characterized is a hepta-B-glucoside elicitor. Induction of phytoalexin accumulation by the hepta-B-glucoside elicitor is an excellent model system for the study of the structure and function of oligosaccharide receptors in plants because the complete structure of the oligosaccharide ligand has been determined and considerable information is known about the genes whose transcription is induced in plant cells upon binding of the oligosaccharide. The proposed studies, if successful, will be particularly important in plants, since plant receptors for regulatory molecules have not yet been purified and characterized.***//

这项研究的目的是分离和表征 生物活性七-B-葡糖苷的受体。 一 放射性标记的七-B-葡糖苷诱导剂，用于配体- 结合研究，将通过缀合 寡糖转化为酪胺，然后碘化 共轭 已经确定， 七葡糖苷、麦芽七糖可以与酪胺缀合 此外，结构的修改， 放射性标记所需七-B-葡糖苷诱导剂 碘不太可能影响其激发子活性。 一 用于受体定位的光亲和标记试剂， 还将编写鉴定研究报告。 的 七-B-葡糖苷诱导剂的受体将是 使用标准细胞分离鉴定和定位 技术、配体结合测定和光亲和性 标签。 如果一个激发子受体被鉴定出来， 纯化和表征。 拟议的实验将 为今后的研究奠定基础， 受体的生理意义，并确定 受体在信号通路中的作用， 导致基因表达的改变，反过来， 在受影响的植物细胞中积累植物抗毒素。% 来源于真菌的β-葡聚糖，其活性成分来源于真菌的β-葡聚糖， 七-B-葡糖苷被分离出来，作为诱导剂或 植物中多种防御机制的增强剂。 的 仅具有生物活性的B-葡聚糖衍生片段， 纯化至均一并进行结构表征 是一种七-B-葡萄糖苷诱导剂。 植物抗毒素的诱导 通过七-B-葡萄糖苷诱导剂的积累是一种 优秀的模型系统的研究结构和 寡糖受体在植物中的功能， 寡糖配体的完整结构已经被 已知的和大量的信息， 其转录在植物细胞中被诱导的基因， 寡糖的结合。 建议的研究，如果 成功，将是特别重要的植物，因为 调节分子的植物受体还没有被 纯化和表征。*//