Molecular responses of higher plants to dehydration

Abstract

A massive amount of data has been accumulating on the molecular responses of plants to water deficit. In plants, dehydration activates a protective response to prevent or repair ensuing damage to cells. The plant hormone, abscisic acid plays a central role in this process. The genetic model Arabidopsis thaliana tolerates a low level of dehydration. Analysis of the abscisic acid signalling pathway and of pathways induced by dehydration in A. thaliana have made a major contribution to our knowledge of the molecular responses of plants to dehydration. Desiccation tolerance is a trait found in the seeds of most higher plants, but also at the level of the whole plant in some species, such as the resurrection plant Craterostigma plantagineum. Here, we discuss the molecular responses to dehydration and desiccation, from the sensing and signalling of water deficit to the regulation of gene expression, focusing mainly on the model systems A. thaliana and C. plantagineum.