Table 1.
Selected genes/gene families involved in salinity stress response.
| Stress Perception / Sensory Proteins | ||
|---|---|---|
| Gene/gene Family | Function | Reference |
| AtAHK1 | Positive regulator of osmotic stress response. Capable of function as an osmosensor in yeast. Mechanism of action still unknown. | [115, 116] |
| AtOSCA1 | Plasma membrane localized calcium channel. Stimulates intracellular Ca2+increase upon osmotic stress imposition. Putative osmosensor. | [119] |
| SOS3 | Ca2+ sensing and downstream activation of the SOS-pathway. | [128] |
| Kinases | ||
| Gene/gene Family | Function | Reference |
| Calcium dependent protein kinases (CDPKs) | Mediate salinity induced calcium signaling through protein phosphorylation. | [129] |
| Mitogen-activated protein kinases (MAPKs) | Stress signaling through activation of transcription factors. | [130] |
| Histidine Kinases (HKs) | Function as receptors for ethylene and cytokinin. AtHK1 also function as putative osmosensors | [115, 116] |
| Sucrose non-fermenting related kinases (SnRK1) | Key component of the ABA- dedendent stress response pathway. SOS2 is an SnRK. | [131] |
| Transcription Factors | ||
| Gene/gen Family | Function | Reference |
| Dehydration responsive element binding proteins/C-element binding factors (DREB/CBF) | Except for CBF-4, DREB/CBFs Mediate ABA-independent regulation of gene expression under osmotic stress. | [132] |
| WRKY transcription factors | WRKY proteins belong to Zinc finger sub family of transcription factors. They have differential roles in the regulatation of ABA-dependent abiotic stress responses. | [133] |
| NAC transcription factors | Stress responsive transcription factors involved in both ABA-dependent and ABA-independent signaling pathways | [134] |
| Leucine basic zipper (bZIP) transcription factors | bZIP transcription factors are part of the ABA-dependent signaling in responses to drought and high salinity. | [135] |
| MYB/MYC transcription factors | MYB/MYC transcripton factors are key elements of the ABA-dependent signal transduction pathway under abiotic stress response. | [136] |
| Ion Channels | ||
| Gene/gene Family | Function | Reference |
| Non selective cation channels (NSCC) | Na+ entry into the roots during high salinity | [137, 138] |
| High affinity potassium transporters subfamily-1 (HKT1) | Na+ entry into root cells under salinity as well as intake of Na+ from the xylem into root cells. | [138, 138] |
| SOS1 | Plasma membrane localized Na+ /H+ antiporter for NA+ efflux from cells. | [137, 138] |
| The NHX-type cation/H+ antiporters | The NHX antiporters are responsible for generating pH gradients and also facilitate Na+ sequestration into the vacuole under ionic stress. | [137-139] |