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Main conclusion: Expression of TaSnRK2.7 promoter is strongly induced under abiotic stress and could be used as a valuable tool for improving plant stress resistance via transgenic techniques.The sucrose non-fermenting 1-related protein kinase 2 (SnRK2) gene family plays pivotal roles in response to abiotic stresses (drought, salinity and cold). Here, we studied the expression of five wheat TaSnRK2.7 promoter-5′-deletion constructs (− 2547, − 1621, − 806, − 599, and − 254) fused to beta-glucuronidase (GUS) in Arabidopsis. Tissue-expression analysis revealed that the − 254 to ATG fragment was sufficient for inducing GUS expression in hypocotyls. Additionally, the − 806 to − 599 and − 2547 to − 1621 fragments contained leaf- and root-specific elements, respectively. Deletion analysis showed that these fragments were unresponsive to ABA treatment, suggesting that TaSnRK2.7 participates in an ABA-independent signaling pathway. Assays examining stress responses of constructs demonstrated that the − 599 to − 254 and − 806 to − 599 fragments contained elements responsive to abiotic and osmotic stress, respectively. The TaSnRK2.7 promoter contained enhancers from − 806 to − 254 and − 2547 to − 1621, while the − 1621 to − 806 fragment contained negative regulatory elements that restrict root and leaf gene expression in response to abiotic stress. Furthermore, under drought and salt stress, the TaSnRK2.7 promoter conferred greater gene expression in leaves than the rd29A promoter, even though both were induced by abiotic stress. These findings enhance our understanding of the molecular mechanisms behind TaSnRK2.7 action, which should prove useful in transgenic studies investigating stress-induced gene expression. [ABSTRACT FROM AUTHOR]

SnRK2 is a plant-specific protein kinase family involved in abiotic stress signalling. In this study, NtSnRK2.1, NtSnRK2.2, and NtSnRK2.3, were cloned from tobacco by in silico cloning and reverse transcription PCR. The three protein kinases were classed into subfamily II of the SnRK2 family using a phylogenetic tree and C-terminus analysis. Subcellular localization revealed NtSnRK2s in the nuclear and cytoplasmic compartments. Dynamic expression of NtSnRK2s in tobacco plants that were exposed to drought, salt, or cold stressors were characterised using quantitative real-time PCR. It was revealed that the three genes showed similar patterns of transcription under abiotic stress responses; there was evidence NtSnRK2s participated in abscisic acid-dependent signalling pathways. NtSnRK2.1- 3 responded much faster to drought and salt than to cold stress. To investigate the role of NtSnRK2s under abiotic stresses, NtSnRK2.1 gene was over-expressed in tobacco. A stress tolerance assay showed that tobacco plants that over-expressed NtSnRK2.1 plants had greater salt tolerance. The results indicate that NtSnRK2s are involved in abiotic stress response pathways. [ABSTRACT FROM AUTHOR]