Drought stress signaling network

Abstract

Stress signaling networks in drought responses are composed of intracellular signaling systems, transcriptional regulatory complexes, and intercellular communication systems. The signaling mechanisms underlying changes in gene expression enable plant responses to drought stress. Signaling factors and transcription factors are themselves regulated transcriptionally and/or posttranslationally (e.g., phosphorylation or proteolysis) in response to drought stress. Abscisic acid (ABA) is a key phytohormone, and ABA signaling is a major part of the drought response regulatory networks. However, ABA-independent pathways are also involved. The complexity of and cross talk between ABA-dependent and ABA-independent pathways in drought stress signaling networks have been extensively analyzed at the cellular level, but not at the intercellular level. Intercellular signaling in response to water deficit has to be elucidated for a comprehensive understanding of plant responses and adaptation to drought stress.