Elucidating how drought stress reprograms genome activity

阐明干旱胁迫如何重新编程基因组活性

基本信息

批准号：
10229336
负责人：
Charles Anthony Seller
金额：
$ 6.64万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-06-01 至 2023-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10229336
关键词：
Abscisic Acid Address Anabolism Biological Biological Assay Biological Models Biology Biophysics Biosensor Cell Nucleolus Cells Chromatin Chromatin Structure Confocal Microscopy DNA Data Set Dehydration Development Dimensions Droughts Environment Eukaryota Exhibits Fluorescence Resonance Energy Transfer Frequencies Future Gene Activation Gene Expression Genes Genetic Genetic Models Genetic Screening Genetic Transcription Genome Genomics Growth Health Histones Homeostasis Homologous Gene Hormones Hour Human Image Impairment Knowledge Libraries Life Style Liquid substance Logic Mediating MicroRNAs Molecular Mouse-ear Cress Multigene Family Nuclear Nuclear Structure Nucleic Acid Regulatory Sequences Nucleosomes Optics Organism Pathway interactions Physiological Physiology Plant Genome Plant Model Plant Roots Plants Property RNA RNA interference screen Regulation Reproduction Research Resistance Resolution Ribosomal RNA Role Severities Signal Pathway Signal Transduction Soil Source Stress System Testing Thinking Time Tissues Work base biological adaptation to stress cell type climate change confocal imaging differential expression experience experimental study genome-wide genomic data hormonal signals improved mutant novel nutrition plant growth/development programs response screening transcription factor transcriptional reprogramming transcriptome

项目摘要

Project Summary Organisms evolved to survive and reproduce in an environment that changes along many dimensions. As a consequence, genomes respond to environmental stress through major alterations in gene expression. In eukaryotes, environmental and developmental signals interact with the genome through chromatin, thus understanding the role of chromatin structure in the activation of stress dependent gene expression programs is crucial. Therefore, we need new studies dissecting the mechanisms controlling stress responses that are well grounded in organismal physiology. Plants provide a unique opportunity to address this issue. To support a sessile lifestyle, plants evolved sophisticated mechanisms to adjust their growth and physiology to confront environmental challenges such as drought, a major limitation on plant growth. Importantly, both the frequency and severity of droughts will likely increase in the near future due to climate change. In dry soil plant cells experience osmotic stress which triggers the differential expression of thousands of genes, a reprogramming of gene expression known as the osmotic stress response. Stressed plant tissues accumulate the hormone abscisic acid (ABA), and ABA signaling further coordinates drought stress transcriptional responses. Despite the massive scale of these transcriptional changes we know little about their accompanying regulation by chromatin structure nor is it clear how ABA hormone signaling is integrated into the larger osmotic stress response. Additionally, our knowledge of the transcriptional regulators mediating the osmotic stress response is far from complete. Using the reference plant Arabidopsis thaliana, a powerful genetic model system, the proposed research will uncover the regulatory program mediating the response to osmotic stress in plant roots. The specific aims of the proposal are: (1) To test if osmotic stress driven changes in chromatin structure prime the genome for subsequent stress hormone induced gene expression using cell type specific genomics. (2) To carry out a focused RNAi screen to identify novel transcriptional regulators functioning in the osmotic stress response. (3) To directly visualize the impact of osmotic stress on nuclear structure and dynamics using confocal microscopy on live plant roots.

项目概要生物体的进化是为了在多维度变化的环境中生存和繁殖。作为一个结果，基因组通过基因表达的重大改变来应对环境压力。在真核生物、环境和发育信号通过染色质与基因组相互作用，因此了解染色质结构在应激依赖性基因表达程序激活中的作用至关重要。因此，我们需要新的研究来剖析控制应激反应的机制具有良好的有机生理学基础。植物为解决这个问题提供了独特的机会。支持在固着的生活方式中，植物进化出了复杂的机制来调整其生长和生理机能以应对干旱等环境挑战是植物生长的主要限制。重要的是，频率由于气候变化，在不久的将来干旱的严重程度可能会加剧。干燥土壤中的植物细胞经历渗透压，触发数千个基因的差异表达，重新编程基因表达称为渗透应激反应。受压力的植物组织会积累激素脱落酸 (ABA) 和 ABA 信号进一步协调干旱胁迫转录反应。尽管这些转录变化的大规模，我们对其伴随的调控知之甚少染色质结构也不清楚 ABA 激素信号如何整合到更大的渗透压中回复。此外，我们对介导渗透应激反应的转录调节因子的了解还远未完成。利用参考植物拟南芥（Arabidopsis thaliana）这一强大的遗传模型系统，拟议的研究将揭示调节植物根部渗透胁迫反应的调节程序。该提案的具体目标是：（1）测试渗透压是否驱动染色质结构的变化使用细胞类型特异性基因组学为随后的应激激素诱导基因表达准备基因组。 (2) 进行有针对性的RNAi筛选，以确定在渗透压中发挥作用的新型转录调节因子应激反应。 (3) 使用以下方法直接可视化渗透胁迫对核结构和动力学的影响活植物根部的共聚焦显微镜。