Molecular responses of plants to cold shock and cold acclimation.

The Plant Kingdom encompasses a grouping of mostly sessile organisms that show extreme variation in morphology, size, ecological adaptation, life cycle, and climatic tolerance. With the exception of low elevation tropical environments, plants living just about anywhere else in the world may be subject to temperatures below that which are optimal for growth and survival. Consequently, the range of tolerance to low temperature stress in the Plant Kingdom is as great as the natural variation in low temperatures. For mesophilic plants, sub-optimal low temperature could range from 15 degrees C down to -55 degrees C. In the past 10 years, more than 100 genes have been shown to be preferentially expressed in response to low temperatures. Significant progress in understanding the responses of plants to low temperature has occurred in the areas of signal perception and transduction pathways, transcriptional control and the characterization of a variety of stress-related proteins. A common aim of much of the research on cold stress in plants is to find ways to enhance the stress tolerance and reduce economic losses.