Role of the Two-Component Pathway in Mediating Ethylene Signal Transduction

二元途径在介导乙烯信号转导中的作用

• 批准号: 1456487
• 负责人: George Schaller
• 金额: $ 60万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1456487&HistoricalAwards=false
• 关键词: Role; Two; Component; Pathway; Mediating

The plant hormone ethylene plays important and wide-ranging roles throughout plant growth and development, including regulation of seed germination, seedling growth, leaf and petal abscission, fruit ripening, organ senescence, and pathogen responses. How a single hormone mediates such a diverse array of processes and how these processes are integrated with other signaling pathways remain fundamental questions in plant biology. This project will explore a gene expression mechanism by which ethylene regulates such processes, thereby providing novel insights into ethylene signaling and regulation as well as avenues by which to modify ethylene responses in agriculturally important plants. A summer art-and-science course titled "Secrets of the Green World" will be developed in conjunction with this project, where students will employ scientific tools, engage in scientific thought, and be involved in a creative process that integrates science with art.The established pathway for ethylene signal transduction culminates in transcriptional regulation by the EIN3 family of transcription factors (TFs). Evidence indicates that the ethylene receptors may also signal through a two-component pathway, employing the type-B ARR family of TFs, to control a subset of the ethylene responses. This project presents an integrated set of experiments to determine how the type-B ARRs function in concert with the EIN3 family of TFs, building toward a systems level understanding of the ethylene transcriptional response. The first objective of this project is to characterize the role of physical interaction between type-B ARRs and EIN3 in transcriptional regulation. Mechanistic studies will be pursued to elucidate the basis for the interaction and how this interaction affects ethylene-dependent gene regulation. The second objective is to determine the suite of genes co-regulated by type-B ARRs and EIN3. ChIP-Seq and RNA-Seq based approaches will be used to identify the co-regulated targets, and systems-based approaches used to predict physiological roles for testing. The third objective is to characterize transcriptional cross-talk between the ethylene and cytokinin signaling pathways, since employment of two-component signaling elements by the ethylene pathway is predicted to affect signaling through the cytokinin pathway. Models for how TF cooperativity and sequestration regulate cross-talk between these phytohormone signaling pathways will be tested using transcriptomic and genetic approaches.

植物激素乙烯在整个植物生长发育过程中起着重要而广泛的作用，包括调节种子萌发、幼苗生长、叶片和花瓣脱落、果实成熟、器官衰老和病原体反应。一种激素如何介导如此多样的过程以及这些过程如何与其他信号通路整合仍然是植物生物学中的基本问题。该项目将探索乙烯调节这些过程的基因表达机制，从而为乙烯信号传导和调节以及改变农业重要植物中乙烯反应的途径提供新的见解。一个夏季的艺术和科学课程，题为“绿色世界的秘密”将与这个项目一起开发，在那里学生将采用科学工具，从事科学思想，并参与一个创造性的过程，将科学与艺术相结合。乙烯信号转导的既定途径最终在转录调控EIN 3家族的转录因子（TF）。有证据表明，乙烯受体也可能通过双组分途径，采用B型ARR家族的TF，控制乙烯反应的子集。该项目提出了一套完整的实验，以确定B型ARRs如何与EIN 3家族的TF一起发挥作用，建立对乙烯转录反应的系统水平理解。本项目的第一个目标是描述B型ARR和EIN 3之间的物理相互作用在转录调控中的作用。将进行机制研究，以阐明相互作用的基础，以及这种相互作用如何影响乙烯依赖的基因调控。第二个目标是确定由B型ARR和EIN 3共同调节的基因组。基于ChIP-Seq和RNA-Seq的方法将用于鉴定共调节靶标，基于系统的方法用于预测测试的生理作用。第三个目标是表征乙烯和细胞分裂素信号传导途径之间的转录串扰，因为预测乙烯途径的双组分信号传导元件的使用会影响通过细胞分裂素途径的信号传导。TF协同性和隔离如何调节这些植物激素信号通路之间的串扰模型将使用转录组学和遗传学方法进行测试。