ABSTRACT

Drought stress-induced sensing-signalling pathways trigger post-translational modifications of chromatin, transcription factors and gene transcriptional and post-transcriptional regulatory networks in order to mitigate damaging effects of stress by activating plant defense mechanisms. Regulation of gene expression and metabolic engineering of plants play critical roles in maintaining plant performance under stress conditions. Among the metabolic pathways, understanding the roles of redox, protein (mainly functional proteins and regulatory proteins) carbohydrate, osmolyte, and phytohormone homeostasis are of considerable importance for optimizing plant responses to drought stress. In this regard, this review discusses some essential aspects of metabolic pathways. These include early protein phosphorylation/dephosphorylation, regulation of the genes that encode RNA binding proteins and aquaporins, the enzyme and carbohydrate metabolism that protect cells against oxidative damage and promote osmoprotection, energy status, and photosynthesis in drought-stressed cells in order to provide insights for developing drought tolerant crops.