The role of histidine in plant development

组氨酸在植物发育中的作用

• 批准号: 0419745
• 负责人: Thomas Leustek
• 金额: --
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0419745&HistoricalAwards=false
• 关键词: role; histidine; plant; development

PROJECT SUMMARYThe proteins in all living organisms are constructed using a set of twenty different amino acids, and plants serve as the primary source of these protein building blocks in the human diet. Plants also use specific amino acids in a variety of other ways including combating insect pests, plant diseases, and surviving environmental hardship. Therefore, it is ultimately important to understand how plants supply amino acids to their various organs. One example of this importance relates to the nutritional quality of seeds. Amino acid content is an important factor affecting the nutritional value of seed crops. Knowing how amino acids are accumulated in seeds, whether they are produced endogenously or are delivered there from elsewhere in the plant, would be critical to devising strategies to improve nutritional quality.This proposal focuses on the amino acid histidine. Examination of mutants of the plant species Arabidopsis thaliana that are unable to synthesize histidine showed that they die at the earliest stages of seed development. The mutants die even if they are borne by a maternal plant that is able to produce histidine. This observation suggests that the maternal plant cannot supply this amino acid to its seeds. The aim of the current proposal is to learn how histidine is accumulated in seeds. To address this issue a series of experiments are proposed to explore the following questions. If the parent plant cannot supply histidine, is it because this amino acid is actively excluded from developing seeds, or is it because the parent plant does not produce enough histidine to supply its seeds? If histidine is actively excluded, why is this so? Is it an indication that histidine plays some special role in seed development and if so, what is this function? If developing seeds produce their own histidine, what genes are necessary for the process and how does the expression of these genes control histidine production?Intellectual MeritThe current proposal challenges common presumptions on how amino acids are supplied for seed development. Until now it was thought that all of them are supplied to developing seeds by the maternal plant. Apparently this is not true for histidine. Studying how plants allocate histidine will lead to insights into the allocation of other amino acids. Therefore, the proposed work will expand our understanding of how plants control synthesis and utilization of amino acids, processes that are essential for the growth and development of plants, and to human use of plant resources. Broader ImpactsThe proposed activities will provide research and training for a postdoctoral fellow, undergraduates, and high school students. Laboratory experiences for undergraduates and high school students in particular are critical for the training of future scientists, policy makers, and informed citizens. The P.I. has a strong track record of involving undergraduate and high school students in vibrant research projects. The students are frequently from demographic groups that are underrepresented in the biological sciences. Moreover, the "educational" mindset in the P.I.'s group translates into opportunities for the postdoctoral fellow to develop teaching skills.

所有生物体中的蛋白质都是由一组20种不同的氨基酸组成的，植物是人类饮食中这些蛋白质的主要来源。 植物还以各种其他方式使用特定的氨基酸，包括对抗昆虫害虫，植物疾病和在环境困难中生存。 因此，最终重要的是要了解植物如何为其各种器官提供氨基酸。 这种重要性的一个例子涉及种子的营养质量。 氨基酸含量是影响种子作物营养价值的重要因素。 了解氨基酸是如何在种子中积累的，无论它们是内源性产生的还是从植物的其他地方传递到种子中的，对于设计改善营养质量的策略至关重要。 对不能合成组氨酸的植物物种拟南芥突变体的研究表明，它们在种子发育的最早阶段死亡。 突变体即使由能够产生组氨酸的母体植物携带也会死亡。 这一观察结果表明，母体植物不能为其种子提供这种氨基酸。 目前的建议的目的是了解组氨酸是如何在种子中积累。 为了解决这个问题，提出了一系列的实验来探索以下问题。 如果亲本植物不能提供组氨酸，是因为这种氨基酸被积极地排除在发育的种子之外，还是因为亲本植物不能产生足够的组氨酸来供应它的种子？ 如果组氨酸被主动排除，为什么会这样？ 这是否表明组氨酸在种子发育中起着某种特殊的作用？如果是，这种作用是什么？ 如果发育中的种子产生自己的组氨酸，什么基因是必需的过程，这些基因的表达如何控制组氨酸的生产？智力价值目前的建议挑战了关于如何为种子发育提供氨基酸的常见假设。 到目前为止，人们认为所有这些都是由母体植物提供给种子发育的。 显然，这对组氨酸不是真的。 研究植物如何分配组氨酸将有助于了解其他氨基酸的分配。 因此，拟议的工作将扩大我们对植物如何控制氨基酸合成和利用的理解，这些过程对植物的生长和发育以及人类利用植物资源至关重要。更广泛的影响拟议的活动将为博士后研究员、本科生和高中生提供研究和培训。 特别是本科生和高中生的实验室经验对于培养未来的科学家，政策制定者和知情公民至关重要。 私家侦探在本科生和高中生参与充满活力的研究项目方面有着良好的记录。 这些学生通常来自生物科学中代表性不足的人口群体。此外，P.I.中的“教育”心态。的小组转化为博士后研究员发展教学技能的机会。