Ethylene Signaling and Transcriptional Networks that Control Root Development

许多生物体依靠激素信号网络来控制生长，发育和对环境的反应。本研究将利用系统生物学方法揭示乙烯介导的拟南芥基因表达网络。乙烯在调节植物在胁迫环境中的生长以及果实成熟过程中具有重要作用。该项目将深入了解根系发育的激素控制，从而具有重要的农业意义，因为根系结构决定了从土壤中吸收水分和养分的效率。本研究所开发的分子生物学和建模方法可以应用于其他信号网络和植物物种。 在更广泛的影响方面，本科生和研究生研究人员将接受生物化学，遗传学，数学和计算机科学接口的培训。该项目将支持和扩大一个正在进行的服务学习计划，本科生物实验室的学生通过对孟德尔和分子遗传学的积极学习练习，使用乙烯信号缺陷的植物教初中和高中学生。本项目的目标是利用乙烯受体的无效突变体揭示拟南芥中控制多个根乙烯反应的乙烯受体下游的转录网络。乙烯调节的，全基因组的数据集测量根样品中的转录丰度的时间变化将被用来确定顺序诱导的转录本编码转录因子参与根发育过程。贝叶斯建模将用于识别模式和时间关系，以预测转录网络，这将使用遗传方法以迭代方式进行验证。 乙烯调控的转录因子的结合位点将通过计算和实验方法来确定。更广泛的影响包括学生的研究培训和服务学习项目，其目标是通过教授高中生让非专业本科生参与科学。该项目将支持协调和组织学校访问，评估本科生的学习成果，并将该计划传播到其他学术机构。

Many organisms rely on hormone signaling networks to control growth, development, and responses to their environment. In this project a systems biology approach will be used to reveal the Arabidopsis thaliana gene expression networks that control plant developmental changes mediated by ethylene, a gaseous plant hormone. Ethylene has important roles in modulating plant growth in stressful environments, as well as during fruit ripening. This project will provide insight into the hormonal controls of root development thereby having important agricultural implications, as root architecture determines the efficiency of moisture and nutrient uptake from soil. The molecular biology and modeling approaches developed in this project can be applied to other signaling networks and plant species. In terms of broader impacts, undergraduate and graduate student researchers will receive training at the interface of biochemistry, genetics, mathematics, and computer science. The project will support and expand an on-going service-learning program where undergraduate biology laboratory students teach middle and high school students through an active learning exercise on Mendelian and molecular genetics using plants with defects in ethylene signaling. The goal of this project is to uncover the transcriptional networks downstream of the ethylene receptors that control multiple root ethylene responses in Arabidopsis thaliana using null mutants of ethylene receptors. An ethylene-regulated, genome-wide data set measuring temporal changes in transcript abundance in root samples will be utilized to identify sequentially induced sets of transcripts encoding transcription factors involved in root developmental processes. Bayesian modeling will be utilized to identify patterns and temporal relationships to predict transcriptional networks, which will be validated using genetic approaches, in an iterative fashion. Binding sites of ethylene-regulated transcription factors will be identified by computational and experimental approaches. The broader impacts include both student research training and a service-learning project with the goal of engaging non-major undergraduates in science through teaching high school students. This project will support the coordination and organization of school visits, assessment of learning outcomes for undergraduates, and dissemination of this program to other academic institutions.