To investigate the function of OsST2, a candidate gene associated with seedling-stage salt tolerance, and to elucidate its molecular mechanism in regulating salt tolerance in rice, an analysis under salt stress conditions was conducted.
The CRISPR-Cas9 gene editing technology was used to generate OsST2 knockout mutants, and the phenotypic and physiological characteristics of these mutants under salt stress were analyzed.
Under salt stress, the OsST2 gene knockout mutants exhibited significant changes in traits such as seedling height, dead leaf rate, root traits, and leaf SPAD value compared to the wild type. Moreover, the OsST2 knockout mutants demonstrated stronger salt tolerance than the wild type. qRT-PCR analysis revealed that the relative expression levels of known genes positively regulating rice salt tolerance, such as SKC1, OsMYB84, OsNAC3, OsMsr9, and ROS-related genes, were significantly higher in the OsST2 knockout mutants compared to the wild type. After salt stress, the levels of malondialdehyde, hydrogen peroxide, and superoxide anion in the OsST2 knockout mutants were significantly lower than those in the wild type. Conversely, the activities of peroxidase and superoxide dismutase, as well as glutathione content, were significantly higher in the mutants compared to the wild type. These findings suggest that the knockout of OsST2 enhances the rice plant's ability to scavenge reactive oxygen species, thereby improving its salt tolerance.
OsST2 negatively regulates salt tolerance in rice. Loss of OsST2 function enhanced the scavenging capacity of ROS in rice, thereby improving salt tolerance in rice, confirming that OsST2 plays an important role in the regulation of salt tolerance in rice.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |