RUI: Regulation of starch degradation by the pseudoamylase, BAM9

RUI：假淀粉酶 BAM9 对淀粉降解的调节

• 批准号: 2322867
• 负责人: Christopher Berndsen
• 金额: $ 63.36万
• 依托单位: James Madison University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2322867&HistoricalAwards=false
• 关键词: RUI; Regulation; starch; degradation; pseudoamylase

Plant starch is an important molecule for humans. In addition to being a primary source of nutrition for humans and many domestic animals, humans use starch in the laundry, food, pharmaceutical, and paper making industries. Despite the widespread use, our understanding of how starch is synthesized and degraded by plants is limited. Both processes affect the shape and form of starch, which affects the way the starch can be used by humans. This project aims to understand the regulation of starch degradation in the model plant Arabidopsis thaliana. This plant has several enzymes called amylases that degrade starch with distinct activities and apparent functions. This project will describe the molecular and biochemical action of two types of amylases, beta and alpha, as they work together to degrade starch during plant stress. One of the project’s goals is to develop new insights into how the structure of starch is controlled in plants. The experiments in this project will be carried out at a predominately undergraduate institution and involve at least 15 undergraduate students. These students will perform a majority of the experiments and develop their technical and professional skills as scientists which will aid them for future graduate education and careers in science. Additionally, teachers and students at a local elementary school will participate in a research project to develop the students’ understandings of the scientific process.Starch is a complex biomolecule composed of two distinct sub-structures, amylose and amylopectin, which are polymers of glucose with different levels of branching. Starch accumulates and is degraded through several different mechanisms that are dependent on the plant species, plant tissue, and external factors such as time of day and stress. While there is a general understanding of these mechanisms, many of the details including the specific stimuli and regulatory steps of starch synthesis and degradation are unclear. This project aims to detail the structural, biochemical, and molecular mechanism for the involvement of the beta-amylase BAM9 in regulated starch degradation. This protein does not have apparent starch degrading activity but does appear to enhance the activity the alpha amylase, AMY3. This project will characterize how BAM9 interacts with AMY3 and the activation mechanism of BAM9. Further experiments will identify and describe the cellular events that regulate BAM9 leading to activation of AMY3 and starch degradation in response to stress. Ultimately, this project will provide the first biochemical and mechanistic characterization of the pseudo-amylase BAM9, and more broadly, how regulated enzyme complexes degrade starch.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

植物淀粉是人体的重要分子。除了作为人类和许多家畜的主要营养来源之外，人类还在洗衣、食品、制药和造纸工业中使用淀粉。尽管淀粉被广泛使用，但我们对植物如何合成和降解淀粉的了解有限。这两个过程都会影响淀粉的形状和形式，从而影响人类使用淀粉的方式。本研究旨在了解模式植物拟南芥淀粉降解的调控机制。这种植物具有几种称为淀粉酶的酶，它们以不同的活性和明显的功能降解淀粉。这个项目将描述两种类型的淀粉酶，β和α的分子和生物化学作用，因为它们在植物胁迫期间共同降解淀粉。该项目的目标之一是对植物中淀粉的结构如何控制提出新的见解。该项目的实验将在一所以本科为主的机构进行，至少有15名本科生参与。这些学生将进行大部分实验，并发展他们的技术和专业技能，作为科学家，这将有助于他们未来的研究生教育和科学事业。此外，当地一所小学的教师和学生将参与一项研究项目，以培养学生对科学过程的理解。淀粉是一种复杂的生物分子，由两种不同的亚结构组成，即直链淀粉和支链淀粉，它们是葡萄糖的聚合物，具有不同的分支水平。淀粉通过几种不同的机制积累和降解，这些机制取决于植物物种、植物组织和外部因素，如一天中的时间和胁迫。虽然对这些机制有一个普遍的理解，但许多细节，包括淀粉合成和降解的特定刺激和调节步骤尚不清楚。该项目旨在详细说明β-淀粉酶BAM 9参与调节淀粉降解的结构，生化和分子机制。这种蛋白质不具有明显的淀粉降解活性，但似乎增强α淀粉酶AMY 3的活性。该项目将描述BAM 9如何与AMY 3相互作用以及BAM 9的激活机制。进一步的实验将鉴定和描述调节BAM 9的细胞事件，其导致响应于应激的AMY 3活化和淀粉降解。最终，该项目将提供假淀粉酶BAM 9的第一个生化和机械特性，以及更广泛地说，受管制的酶复合物如何降解淀粉。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。