Plants ‘remember’ how to deal with drought

Plants subjected to repeated periods of drought can remember how to deal with the stress according to an article published online this week in Nature Communications. The study shows that subsets of stress-response genes are trained to alter their activity according to the availability of water. This discovery may lead to approaches that could improve a plant’s ability to deal with changing environments. When subjected to stress plants can modify their behaviour and can improve their reactions to recurring insults. For example, plants may change gene expression patterns, which are controlled by a process called transcription, or they may adjust specific cellular functions. However, the underlying processes involved in this ‘stress memory’ are poorly understood. By repeatedly exposing Arabidopsis to drought, Zoya Avramova and colleagues show that the plants can adjust their ability to retain water. The authors demonstrate that the plants respond by increasing transcription of a certain subset of genes. During recovery periods when water is available transcription of these genes remains at normal levels, but following subsequent drought periods the plants remember their transcriptional response to stress. These findings illustrate the concept of a memory from an earlier stress.