Role of Tomato bHLH Transcription Factors in Development and Immunity

植物的生长受到多种细胞外信号的影响，包括激素、生物钟、发育和环境信号以及病原诱导子。这些信号通过不同的和重叠的信号通路起作用，这已经被广泛研究。然而，控制和整合这些途径之间相互作用的关键因素在基因调控水平上仍然知之甚少。植物在生长和防御之间进行优先权衡的能力对于在不断变化的环境中优化其适应性至关重要。如何在分子水平上调节生长-防御权衡在很大程度上是未知的，并且是植物生物学中的中心问题。最近的证据表明，基本螺旋-环-螺旋（bHLH）类转录因子（TF）在调节控制生长-防御权衡的基因表达网络中发挥重要作用。本项目的目的是研究茄科的代表性作物番茄中未知的bHLH转录因子，为以下方面提供新的认识：（1）在番茄生长和防御中起重要作用的转录通路;（2）调控这些转录通路的因子;以及（3）可以被工程化以增强抗病性同时优化植物适合度的潜在途径。正在进行的国际合作将提供一个框架，以分享新出现的概念、工具和技术。这项研究将在研究生，本科生和高中阶段提供实践研究和指导培训，特别考虑妇女，代表性不足的少数民族，低收入学生和残疾学生。与高中的外联伙伴关系将为教师和学生提供课程开发、实验室升级、技术支持和充实培训。稀疏的信息是关于作物植物中的转录因子（TF）和转录网络，它们整合多种信号以优化适应性，以响应病原体的攻击，以及它们如何被病原体操纵。最近的证据表明，番茄病原体黄单胞菌（Xanthomonaseuvesicatoria）特异性调节基本螺旋-环-螺旋（bHLH）控制的转录回路，动态改变番茄的生长和免疫力，以促进发病。其中一个网络在根中是侧根发育所必需的，并被假设影响养分获取的效率。本研究的主要目的是：（1）利用RNAseq和ChipSeq技术研究控制番茄发育和免疫的DH 1转录网络;（2）确定黄单胞菌如何直接改变控制番茄叶片中DH 1转录的转录复合物，为病原菌在侵染过程中如何操纵TF-模块提供机理见解;和（3）确定在番茄生长和/或免疫中起作用的另外的bHLH TF。这些信息将用于设计新的方法，以优化重要作物的生长。正在进行的国际合作将提供一个框架，以分享新出现的概念、工具和技术。这项研究将在研究生、本科生和高中阶段提供实践研究和指导培训，特别考虑妇女、代表性不足的少数民族、低收入学生和残疾学生。与高中的外联伙伴关系将为教师和学生提供课程编制、实验室升级、技术支持和充实培训。

Plant growth is influenced by multiple extracellular signals including hormones, circadian clock, developmental and environmental cues, and pathogen elicitors. These signals act through distinct and overlapping signaling pathways, which have been studied extensively. The key factors that control and integrate interactions between these pathways however remain poorly understood at the gene regulation level. A plant's ability to prioritize tradeoffs between growth and defense is critical for optimizing its fitness in an ever-changing environment. How growth- defense tradeoffs are regulated at the molecular level is largely unknown and is a central question in plant biology. Recent evidence suggests that transcription factors (TFs) of the basic helix-loop-helix (bHLH) class play important roles in regulating gene expression networks that control growth-defense trade-offs. The goal of this project is to study unknown bHLH TFs in tomato, a representative crop of the Solanaceae and the third most valuable crop family in the world, to provide new knowledge regarding: (1) the transcription circuits that play a major role in tomato growth and defense; (2) the factors that regulate these transcription circuits; and (3) the potential pathways that can be engineered to enhance disease resistance while optimizing plant fitness. Ongoing international collaboration will provide a framework to share emerging concepts, tools and technology. This research will provide hands-on research and mentorship training at the graduate, undergraduate, and high school level with special consideration of women, underrepresented minorities, low-income students, and disabled students. Outreach partnerships with high schools will provide curriculum development, laboratory upgrades, technical support and enrichment training for teachers and students.Sparse information is available about the transcription factors (TFs) and transcription networks in crop plants that integrate multiple signals to optimize fitness in response to pathogen attack and how they are manipulated by pathogens. Recent evidence suggests that the tomato pathogen Xanthomonas euvesicatoria specifically regulates basic helix-loop-helix (bHLH)- controlled transcription circuits to dynamically alter tomato growth and immunity to promote pathogenesis. One of these networks in roots is required for lateral root development and is hypothesized to impact the efficiency of nutrient acquisition. The goals of this research is to: (1) use RNAseq and ChipSeq technologies to study the DH1 transcription network(s) controlling development and immunity in tomato; (2) determine how Xanthomonas directly alters the transcription complex that controls DH1 transcription in tomato leaves to provide mechanistic insight for how pathogens manipulate TF-modules during infection; and (3) define additional bHLH TFs that function in growth and/or immunity in tomato. This information will be used to engineer novel approaches to optimize growth in important crops. Ongoing international collaboration will provide a framework to share emerging concepts, tools and technology. This research will provide hands-on research and mentorship training at the graduate, undergraduate, and high school level with special consideration of women, underrepresented minorities, low- income students, and disabled students. Outreach partnerships with high schools will provide curriculum development, laboratory upgrades, technical support and enrichment training for teachers and students.