Extremes in environmental conditions such as low and high temperature, drought, and high salinity, severely limit the geographical distribution of plants and account in large part for the shortfalls between potential and actual crop yields. Many plants, however, have evolved mechanisms that enable them to acclimate to and survive to varying degrees, different forms of environmental "stress." The long term research interest of the Principal Investigator is to understand at a molecular and cellular level the adaptive responses that plants make to survive cold and freezing temperatures. He has recently established that Arabidopsis, like many other plants, becomes more frost tolerant when exposed to low nonfreezing temperatures and that changes in gene expression occur during this cold acclimation process. His goal now is to determine the functions of the cold-regulated ("cor") genes. His specific aims include: the isolation and sequencing of cor genes; determining whether COR polypeptides have cryoprotective effects; the construction and analysis of Adrabidopsis cor mutants; determining the cellular and subcellular location of the COR gene products; and determining whether Arabidopsis cor genes are highly conserved among plants. At a minimum, these studies should provide additional insight into the molecular and physiological changes that occur in plants at low temperature. They also have the potential of yielding genes that could be used to improve the cold and freezing tolerance of agronomically important plants.
