The brazzein-sweet taste receptor interaction

Brazzein-甜味受体相互作用

• 批准号: 6848878
• 负责人: GORAN B HELLEKANT
• 金额: $ 31.03万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-01 至 2006-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6848878
• 关键词: Macaca mulatta; cell membrane; chemoreceptors; chorda tympani; clinical research; cranial nerves; craving; gene mutation; human subject; obesity; plant proteins; sucrose; taste

DESCRIPTION (provided by applicant): Recent and earlier studies suggest a direct link between obesity, a major cause of morbidity and mortality, sweet taste, and craving for sweet. This craving is generally satisfied with sugars, which are still overwhelmingly preferred, despite availability of a number of non-caloric sugar substitutes. A likely reason for this is that no substitute tastes like sucrose. We predict that there will be none until the molecular mechanism(s) of sweet taste is fully understood. Here we propose to combine the easily modified, high potency sweet plant protein, Brazzein, which we discovered (Ming and Hellekant 1994), with the recently discovered family of transmembrane receptors for sweet taste T1Rs to achieve insight into the peripheral mechanism(s) of sweet taste. This knowledge can then be used to create better non-caloric sugar substitutes and will ultimately serve the clinic. The experimental goals of this proposal are: 1. To generate brazzein mutants for structure-function analyses: a. To design and produce brazzein mutants, b. To examine the structurat and dynamic consequences of the mutations. 2. To characterize the brazzein-taste receptor interaction in vitro and in vivo. a). To test brazzein mutants for direct binding and activity assay with T1R2/T1R3 sweet receptors; b). To record the effects of brazzein mutations on responses from rhesus monkey in single chorda tympani and glossopharyngeal taste fibers, c). To determine the sweetness of the brazzein mutants psychophysically with human subjects. 3. To model the brazzein-taste receptor interaction, a). To homology-model human T1R2/T1R3 extra-cellular domain heterodimers, b). To evaluate possible docking sites for brazzein and brazzein mutants on these extra cellular domain heterodimers. Ming, D. and G. Hellekant (1994). "Brazzein, a new high-potency thermostable sweet protein from Pentadiplandra brazzeana B." FEBS Letters 355(1): 106-8.

描述（由申请人提供）：最近和较早的研究表明，肥胖是发病率和死亡率，甜味和渴望甜食的主要原因之间的直接联系。尽管有多种非过滤糖替代品，但这种渴望通常对糖仍然是绝大多数首选的糖。造成这种情况的一个可能是没有替代品的味道。我们预测，直到完全理解甜味的分子机制之前，将没有。在这里，我们建议将易于改性的高效力甜植物蛋白Brazzein结合在一起，我们发现了这些蛋白（Ming and Hellekant 1994），以及最近发现的跨膜受体家族，用于甜味T1RS，以深入了解甜味的外围机制。然后，这些知识可用于创建更好的非热糖替代品，并最终为诊所服务。该提案的实验目标是：1。生成Brazzein突变体进行结构功能分析：设计和生产Brazzein突变体，b。检查突变的结构和动态后果。 2。表征Brazzein-Taste受体相互作用的体外和体内。 一个）。测试Brazzein突变体与T1R2/T1R3甜受体的直接结合和活性测定； b）。为了记录Brazzein突变对单一弦鼠Tympani和胃咽部味道纤维中恒河猴的反应的影响，C）。用人类受试者在心理上确定Brazzein突变体的甜度。 3。为了建模Brazzein-Taste受体相互作用，A）。对同源模型人类T1R2/T1R3细胞外域异二聚体，b）。评估在这些额外的细胞域异二聚体上的Brazzein和Brazzein突变体的可能对接位点。 Ming，D。和G. Hellekant（1994）。 “ Brazzein，一种来自Pentadiplandra Brazzeana B. FEBS Letters 355（1）：106-8。