Low Temperature Transcriptional Networks

点击翻译按钮获取中文摘要

PI: M. Thomashow (Michigan State University)CoPIs: C. Chan (Michigan State University) and T. Chen (Oregon State University; subawardee)Collaborator: S.-H. Shiu (Michigan State University)The long range goals of the project are to gain a systems level understanding of plant responses to abiotic stress and to use the first principles gained to develop novel strategies to improve the stress tolerance of agriculturally important crops. These goals are important as abiotic stresses limit the geographical locations where crops can be grown and account for the majority of losses in yield on an annual basis. The overall objective is to identify the low temperature transcriptional networks that plants have evolved to survive freezing. As there is a direct link between freezing and dehydration injury, the results should also provide further insights into the nature of gene modules that impart tolerance to drought and other dehydration stresses. The specific aims of the project are two-fold. The first is to develop a detailed understanding of the low temperature transcriptional network of Arabidopsis and determine which components contribute to freezing tolerance. This will be accomplished by identifying transcription factors and other regulatory proteins that have key roles in configuring the low temperature transcriptome; identifying the cis-acting DNA regulatory elements through which these regulatory proteins function; and identifying the regulatory programs and gene modules that contribute to freezing tolerance (and potentially tolerance to drought and other abiotic stresses). The second aim of this project is to determine whether the low temperature transcriptional networks and gene modules that impart freezing tolerance in Arabidopsis are conserved in plants that cold acclimate (i.e., increase in freezing tolerance in response to low non-freezing temperatures) and whether "deficiencies" in these networks and modules contribute to the freezing sensitivity of those plants that do not cold acclimate. This aim will be accomplished through comparative genomic analysis of three closely related Solanum species which differ in cold tolerance: S. commersonii, potato and tomato. Together, the proposed studies incorporate the determination of gene expression at a genome level, a comparative genomic analysis of model and crop species, and the integration of computational analysis and empirical testing to reconstruct and model transcriptional regulatory networks that are fundamental to plant life and have importance in agriculture. Broader ImpactsImproving the abiotic stress tolerance of crops is crucial to meeting future demands for food and fiber. In addition, it is a key component of an emerging national vision to produce sufficient biomass per year in the U.S. to replace significant percentages of petroleum-based transportation fuels with biofuels produced from renewable resources. The studies proposed here directly relate to these important areas as they will provide a deeper understanding of the genomic mechanisms that plants have evolved to cope with abiotic stress and have the potential to provide genetic tools to improve the abiotic stress tolerance of plants. Microarray data generated in the course of these studies will be available through a project website (http://aztec.stanford.edu/cold/index.html) and through GEO and ArrayExpress. The project will also contribute to the training of a next generation of scientists who are experienced in bringing genomic, bioinformatic and computational approaches to bear on fundamental questions in biology. Finally, the project includes a summer undergraduate education and research training program which will target inclusion of underrepresented groups of our society. The goal is to provide the students with opportunities to learn more about different areas of genomic research and to discuss broadly and informally issues that relate to pursuing careers in science.