Key Laboratory of Biology and Genetic Improvement of Sweetpotato, Ministry of Agriculture and Rural Affairs, Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai District, Xuzhou 221131, China.
Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
Int J Mol Sci. 2023 Nov 17;24(22):16454. doi: 10.3390/ijms242216454.
Black rot disease, caused by Ellis & Halsted, severely affects both plant growth and post-harvest storage of sweet potatoes. Invertase (INV) enzymes play essential roles in hydrolyzing sucrose into glucose and fructose and participate in the regulation of plant defense responses. However, little is known about the functions of INV in the growth and responses to black rot disease in sweet potato. In this study, we identified and characterized an gene, named , from sweet potato. IbINV contained a pectin methylesterase-conserved domain. transcripts were most abundant in the stem and were significantly induced in response to , salicylic acid, and jasmonic acid treatments. Overexpressing in sweet potato (OEV plants) led to vigorous growth and high resistance to black rot disease, while the down-regulation of by RNA interference (RiV plants) resulted in reduced plant growth and high sensitivity to black rot disease. Furthermore, OEV plants contained a decreased sucrose content and increased hexoses content, which might be responsible for the increased INV activities; not surprisingly, RiV plants showed the opposite effects. Taken together, these results indicate that IbINV positively regulates plant growth and black rot disease resistance in sweet potato, mainly by modulating sugar metabolism.
黑斑病由 Ellis & Halsted 引起，严重影响甘薯的生长和采后贮藏。转化酶（INV）酶在将蔗糖水解成葡萄糖和果糖方面发挥着重要作用，并参与植物防御反应的调节。然而，关于 INV 在甘薯生长和对黑斑病反应中的功能知之甚少。在这项研究中，我们从甘薯中鉴定并表征了一个基因，命名为 IbINV。IbINV 含有果胶甲酯酶保守结构域。IbINV 转录本在茎中丰度最高，并对 、水杨酸和茉莉酸处理显著诱导。在甘薯中过表达 IbINV（OEV 植株）导致生长旺盛且对黑斑病具有高抗性，而通过 RNA 干扰（RiV 植株）下调 IbINV 的表达导致生长受阻且对黑斑病高度敏感。此外，OEV 植株的蔗糖含量降低，己糖含量增加，这可能是 INV 活性增加的原因；不出所料，RiV 植株表现出相反的效果。综上所述，这些结果表明 IbINV 正向调节甘薯的生长和黑斑病抗性，主要通过调节糖代谢。
