Salt stress seriously restricts the growth and yield of potatoes. Plant cystatins are vital players in biotic stress and development, however, their roles in salt stress resistance remain elusive. Here, we report that StCYS1 positively regulates salt tolerance in potato plants. An in vitro biochemical test demonstrated that StCYS1 is a bona fide cystatin. Overexpression of StCYS1 in both Escherichia coli and potato plants significantly increased their resistance to high salinity. Further analysis revealed that the transgenic plants accumulated more proline and chlorophyll under salt stress conditions. Moreover, the transgenic plants displayed higher H₂O₂ scavenging capability and cell membrane integrity compared with wild-type potato. These results demonstrate that StCYS1 is closely correlated with salt stress and its overaccumulation can substantially enhance salt stress resistance.

盐胁迫严重限制了马铃薯的生长和产量。植物胱抑素在生物胁迫和发育中起着至关重要的作用，但是，它们在抗盐胁迫中的作用仍然难以捉摸。在这里，我们报道StCYS1积极调节马铃薯植株的耐盐性。的体外生物化学试验表明，StCYS1是一个真正的胱抑素。在大肠杆菌和马铃薯植株中StCYS1的过表达显着提高了它们对高盐度的抗性。进一步的分析表明，转基因植物在盐胁迫条件下积累了更多的脯氨酸和叶绿素。此外，转基因植物显示出更高的H ₂ O ₂与野生型马铃薯相比，其清除能力和细胞膜完整性更高。这些结果表明，StCYS1与盐胁迫密切相关，其过量积累可大大增强盐胁迫的抗性。