The betalain secondary metabolic network.

智力优势：甜菜和玫瑰是红色的，原因完全不同。几乎所有开花植物都含有两种互不相容的红/紫色色素途径中的一种，即花青素或甜菜碱。花青素的生物合成/调控网络已经得到了广泛的研究，并存在于绝大多数分类群中，包括禾本科(禾本科)、十字花科(油菜科、芥菜科、油菜科)和蔷薇科(苹果、梨、樱桃)。另一方面，甜菜碱仅限于单一目的某些家族，即石竹目，在所有生物环境中，它们承担花青素的角色。这些作用包括吸引传粉者和种子传播剂，以及在应激和衰老期间作为保护性色素。甜菜属植物的种类和观赏植物遍布世界各地，是许多农业经济系统的重要主食，包括甜菜、菠菜、苋菜、藜麦和花椒仙人掌。这个项目的目的是在分子水平上了解甜菜碱的生物合成和调控网络，以及色素的出现特性是如何产生的。而花青素是以苯丙氨酸为基础的，而甜菜碱则是由氨基酸酪氨酸产生的。在该项目开始之前，研究人员确定了一种新的细胞色素P450酶和一种MYB型转录因子调节因子，它们在甜菜碱网中发挥作用。特别是，将通过沉默甜菜中的基因来测试其功能，并通过甜菜基因在酵母中的表达来测试功能，从而验证关于最后一个未知的甜菜环状结构生物合成酶的身份的假设。一种假设是，甜菜红素受同一组相互作用的蛋白质的调节，这些蛋白质调节其他植物中的花青素色素途径。研究人员将利用甜菜中的基因沉默和过度表达来验证这一假说。花青素受环境信号的调控。贝塔林受这些相同的信号通路调控的假说将得到检验。为了询问环境信号是否通过增加MYB调节基因的表达来发挥作用的问题，我们将用已知的激发子和植物激素或营养剥夺(如磷酸盐)处理植物，并测量所有已知的甜菜碱网络基因的表达。MYB调节子直接与甜菜碱类生物合成基因顺式区域结合的假设将通过蛋白质-DNA结合分析来检验。广泛的影响：这项研究将增强我们对植物次生代谢网络控制的基本理解。甜菜碱是重要的饮食抗氧化剂，具有很高的人体利用率，该项目将导致有能力操纵这一网络，并将途径转移到异源系统中。最终的影响包括创造对人类和牲畜更有营养的作物的能力。该项目将为各级学生提供优秀的培训。这个项目的组成部分是一个新的以探究为基础的新生研究计划流，面向30多名学生，强调科学中的创造性和批判性思维。学生接受假设构建和检验、数据收集、记录保存、统计分析和伦理研究标准等方面的讲授培训。在春季，学生们进入这条小溪，进行两个学期的动手自我指导研究。在过去的十年里，包括本科生和研究生在内的所有实验室成员都参加了当地小学一年一度的科学博览会评委，包括对小学生的互动采访。在过去的六年里，国际和平协会和他的研究生们在学校举办了展会前外展工作坊。在过去的一年里，3名研究生、大约180名四、五年级学生和6名教师参加了关于假设驱动的科学方法、项目构思和项目执行的研讨会。这一外联活动将在整个项目期间继续进行。

Intellectual merit: Beets and roses are red for completely different reasons. Virtually all flowering plants contain one of two mutually exclusive red/purple pigment pathways, anthocyanins or betalains. The anthocyanin biosynthetic / regulatory network has been heavily studied and occurs in the vast majority of taxa including the major crop families: Poaceae (grasses), Brassicaceae (canola, mustards, cole crops), and Rosaceae (apples, pears, cherries). Betalains on the other hand are restricted to certain families of a single order, the Caryophyllales, where they assume the role of anthocyanin pigments in all biological contexts. These roles include attracting pollinators and seed dispersal agents, and as protective pigments during stress and aging. The betalain families contain crop species and ornamentals that are grown worldwide and form important staples in many agricultural economic systems, including Beets, Spinach, Amaranthus, Quinoa, and Prickly Pear cactus. This project is aimed at understanding the betalain biosynthetic and regulatory network at the molecular level and how pigment emergent properties are generated. While anthocyanins are based on the amino acid phenylalanine, while betalains derive from the animo acid tyrosine. Prior to the start of this project, the investigators identified a novel cytochrome P450 enzyme and a MYB-type transcription factor regulator that function in the betalain network. In particular, hypotheses will be tested regarding the identity of the last unknown betalain ring structure biosynthetic enzyme by silencing genes in beet to test their functions and beet gene expression in yeast to test function. One hypothesis is that betalains are regulated by the same set of interacting proteins that regulate the anthocyanin pigment pathway in other plants. The investigators will test this hypothesis using gene silencing and overexpression in beet. Anthocyanin pigments are regulated by well-characterized environmental signals. The hypothesis that betalains are regulated by these same signaling pathways will be tested. In order to ask the question about whether environmental signals work through increasing gene expression of the MYB regulator, plants will be treated with known elicitors and plant hormones, or nutrient deprivation (e.g. phosphate), and expression of all know betalain network genes will be measured. The hypothesis that the MYB regulator directly binds to cis regions of the betalain biosynthetic genes will be tested through protein-DNA binding assays.Broader impacts: This research will enhance our basic understanding of the control of plant secondary metabolic networks. Betalains are important dietary antioxidants with high human availability and this project will lead to an ability to manipulate this network and to move the pathway into heterologous systems. Eventual impacts include the ability to create crops that are more nutritious for humans and livestock. The project will provide excellent training for all levels of students. Integral to this project is a new inquiry-based Freshman Research Initiative stream for 30+ students that emphasizes creative and critical thinking within science. Students receive lecture-based training in hypothesis building and testing, data collection, record-keeping, statistical analysis, and ethical research standards. In the spring, students enter the stream for two semesters of hands-on self-directed research. For the past ten years, all lab members, including undergrad and grad students, have participated in judging yearly science fairs at local elementary schools, including interactive interviews of the elementary students. For the past six years, the PI and his graduate students have conducted prefair outreach workshops at the schools. This past year, 3 graduate students, about 180 4th and 5th graders, and 6 teachers participated in the workshop on hypothesis driven scientific method, project conception, and project execution. This outreach activity will continue throughout the period of this project.