The GRIK-SnRK1 Protein Kinase Cascade And Its Potential Role In Regulating TCP Transcription Factors In Arabidopsis

智力优势：TCPs组成了一个植物特有的转录因子大家族，由保守的基本螺旋-环-螺旋结构域定义。它们分为两类，第一类TCP促进细胞增殖，第二类成员促进叶片和花的分化。TCP是一种序列特异的DNA结合蛋白，以同源或异源二聚体的形式与共享或重叠的基序结合。鉴于tcp家族的复杂性及其联合发挥作用的潜力，它很可能受到一系列错综复杂的监管机制的管理。该项目的总体目标是研究GRIK-SnRK1蛋白激酶级联在TCP调控中的作用。虽然SnRK1在控制和协调植物的碳代谢和能量平衡方面最为著名，但越来越多的证据表明，它也在植物发育中发挥重要作用，并通过磷酸化转录因子来控制植物基因的表达。激活SnRK1的GRIK只在植物幼体组织、培养细胞和双生病毒感染的细胞中积聚，所有这些都复制植物染色体DNA。拟南芥TCP的一部分被GRIK-SnRK1激酶级联磷酸化，SnRK1下调调控的基因中富含I类TCP结合基序。该项目将表征选定的TCPs的GRIK-SnRK1靶残基，并研究其磷酸化状态改变对TCPs功能的影响。这项研究是理解TCPs如何被磷酸化调节以及翻译后机制在调节植物中这个独特的转录因子家族中的作用的重要的第一步。更好地了解TCPs的调控机制和GRIK-SnRK1级联信号通路在Tcp调控中的作用，有助于开发新的策略来调控植物的生长，特别是在代谢胁迫条件下。更广泛的影响：将分子、细胞和生化技术结合起来应用于磷酸三钙的磷酸化，为本科生、研究生和高级研究人员提供了一个独特的培训机会。PIS将共同努力促进其实验室之间的智力和协作互动，以确保参与者受到广泛的培训，并发展必要的技能，以应用综合方法解决复杂的生物问题。项目参与者还将与当地教育工作者和北卡罗来纳州生命科学博物馆合作，为中学教师提供一个为期两天的研讨会，该研讨会基于一种遗传的“行李箱中的科学”工具包。该工具包是为中学年级开始学习遗传学内容的教师设计的补充教学工具，并与NC标准学习课程保持一致，以确保最大限度地发挥潜在的作用。研讨会的主题将包括工具包内容、NC标准课程的学习要求、课堂实施、中学阶段的遗传科学概述以及学习策略的评估。该推广项目有可能惠及北卡罗来纳州格兰维尔和达勒姆县的3600名中学生，这两个县都有大量的少数民族和经济困难学生。更广泛的影响包括聘请30名中学数学和科学教师参加讲习班，通过博物馆工作人员提供后续支持，并在下一学年向参与的教师免费提供工具包。

Intellectual Merit: The TCPs constitute a large family of plant-specific transcription factors that are defined by a conserved basic helix-loop-helix domain. They fall into two classes with Class I TCPs promoting cell proliferation, and Class II members promoting leaf and floral differentiation. TCPs are sequence-specific DNA binding proteins that bind to shared or overlapping motifs as homo- or heterodimers. Given the complexity of the TCP family and its potential to function combinatorially, it is likely to be governed by an intricate array of regulatory mechanisms. The overall goal of the project is to examine the role of the GRIK-SnRK1 protein kinase cascade in TCP regulation. Although SnRK1 is best known for controlling and coordinating carbon metabolism and energy balance in plants, there is increasing evidence that it also plays an essential role in plant development and controls plant gene expression by phosphorylating transcription factors. GRIK, which activates SnRK1, only accumulates in young plant tissues, cultured cells and geminivirus-infected cells, all of which replicate plant chromosomal DNA. A subset of Arabidopsis TCPs are phosphorylated by the GRIK-SnRK1 kinase cascade, and Class I TCP binding motifs are enriched in SnRK1-down regulated genes. The project will characterize GRIK-SnRK1 target residues of selected TCPs and examine the consequence of altering their phosphorylation status on TCP function. This research represents an important first step in understanding how TCPs are regulated by phosphorylation and the role of post-translational mechanisms in modulating this unique transcription factor family in plants. A better understanding of TCP regulatory mechanisms and the role of the GRIK-SnRK1 cascade in TCP control could lead to the development of new strategies for modulating plant growth, especially under metabolic stress conditions. Broader Impacts: The combined application of molecular, cellular and biochemical techniques to TCP phosphorylation provides a unique training opportunity for undergraduate, graduate and senior researchers. The PIs will work together to foster intellectual and collaborative interactions between their laboratories to ensure that participants are broadly trained and develop the skills necessary to apply integrated approaches to complex biological problems. Project participants will also work with local educators and the NC Museum of Life and Science to offer a two-day workshop based on a genetic "Science in a Suitcase" kit for middle school teachers. The kit is designed as a supplemental teaching aid for teachers embarking on genetics content in the middle school grades and is aligned to the NC Standard Course of Study to ensure maximum potential use. Workshop topics will include kit contents, the NC Standard Course of Study requirements, classroom implementation, overview of genetic science at the middle grades level, and assessment of learning strategies. The outreach project has the potential to reach 3,600 middle school students in NC Granville and Durham Counties, both of which have large numbers of minority and economically disadvantage students. The broader impacts include engaging 30 middle grades math and science teachers in the workshops, providing follow-up support through the Museum staff, and providing the kit at no-cost to participating teachers during the following academic year.