Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China.
State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
Plant Cell. 2020 Apr;32(4):1102-1123. doi: 10.1105/tpc.19.00641. Epub 2020 Feb 7.
Cultivated sweet potato () is an important source of food for both humans and domesticated animals. Here, we show that the B-box (BBX) family transcription factor IbBBX24 regulates the jasmonic acid (JA) pathway in sweet potato. When was overexpressed in sweet potato, JA accumulation increased, whereas silencing this gene decreased JA levels. RNA sequencing analysis revealed that IbBBX24 modulates the expression of genes involved in the JA pathway. IbBBX24 regulates JA responses by antagonizing the JA signaling repressor IbJAZ10, which relieves IbJAZ10's repression of IbMYC2, a JA signaling activator. IbBBX24 binds to the promoter and activates its transcription, whereas it represses the transcription of The interaction between IbBBX24 and IbJAZ10 interferes with IbJAZ10's repression of IbMYC2, thereby promoting the transcriptional activity of IbMYC2. Overexpressing significantly increased Fusarium wilt disease resistance, suggesting that JA responses play a crucial role in regulating Fusarium wilt resistance in sweet potato. Finally, overexpressing led to increased yields in sweet potato. Together, our findings indicate that IbBBX24 plays a pivotal role in regulating JA biosynthesis and signaling and increasing Fusarium wilt resistance and yield in sweet potato, thus providing a candidate gene for developing elite crop varieties with enhanced pathogen resistance but without yield penalty.
栽培甘薯（）是人类和家养动物的重要食物来源。在这里，我们表明 B 盒（BBX）家族转录因子 IbBBX24 调节甘薯中的茉莉酸（JA）途径。当 在甘薯中过表达时，JA 积累增加，而沉默该基因则降低 JA 水平。RNA 测序分析表明，IbBBX24 调节参与 JA 途径的基因的表达。IbBBX24 通过拮抗 JA 信号抑制因子 IbJAZ10 来调节 JA 反应，从而解除 IbJAZ10 对 JA 信号激活因子 IbMYC2 的抑制。IbBBX24 结合到 启动子并激活其转录，而抑制 转录。IbBBX24 和 IbJAZ10 之间的相互作用干扰了 IbJAZ10 对 IbMYC2 的抑制，从而促进了 IbMYC2 的转录活性。过表达 显著提高了枯萎病抗性，表明 JA 反应在调节甘薯枯萎病抗性中起关键作用。最后，过表达 导致甘薯产量增加。总之，我们的研究结果表明，IbBBX24 在调节 JA 生物合成和信号以及提高甘薯枯萎病抗性和产量方面发挥着关键作用，因此为开发具有增强的病原体抗性而不牺牲产量的优良作物品种提供了候选基因。
