Low temperature is one of the most common environmental factors influencing the growth, development and survival of plants. Understanding plant responses to low temperature not only helps illuminate fundamental mechanisms of biological low temperature sensing, but also is of critical importance for agriculture because chilling and freezing stresses greatly limit crop production. The long-term goal of this research is to understand the mechanisms of cold sensing and signal transduction in plants. This project focuses on how cold temperatures switch on the expression of genes that are important for plant cold tolerance. Previous work has shown that cold-induction of plant genes is controlled by a transcriptional cascade where cold first triggers the transcription of genes encoding the CBF family of transcriptional factors that in turn activate the expression of a large number of downstream cold-responsive genes. How the CBF genes are induced by cold is currently poorly understood. Preliminary work has identified several Arabidopsis mutants that are impaired in the cold induction of CBF genes. The project will characterize and clone one of the genetic loci defined by these mutants. Gene expression profiling using whole genome microarrays will be carried out on this mutant. The project will lead to the isolation of a critical regulatory gene for low temperature responses. The work will significantly advance our understanding of biological sensing of low temperature cues and enhance our ability to develop rational strategies for engineering chilling and freezing tolerant crops. To broaden the impacts of the research, the project will participate in a summer intern program to train high school science teachers, and will be involved in several other outreach programs by providing plant mutants and luminescence imaging expertise to molecular genetic lab exercises for students; and it will actively recruit and involve undergraduate students in the discovery process.
