Zhang Xiang, Du BingYang, Turupu Maihemuti, Xiao Yuqin, Yao Qisheng, Gai Shilin, Zhang Qiaoqiao, Wang Xinyu, Yan Yongzhen, Wen Zhengyang, Wang Shuo, Lu Wenjun, Yue Pengtao, Li Tianhong
Frontiers Science Center for Molecular Design Breeding, College of Horticulture, China Agricultural University, No.2 Yuanmingyuan West Road, Haidian District, Beijing 100193, China.
Hortic Res. 2025 Apr 9;12(7):uhaf101. doi: 10.1093/hr/uhaf101. eCollection 2025 Jul.
Drought stress limits plant growth, development, and yield in apple (). Strigolactones (SLs) work with abscisic acid (ABA) to improve drought resistance in plants, but how this synergistic mechanism functions remains unclear. Here, we determined that SLs promote drought resistance in apple in an ()-related manner. During drought stress of a wild apple species (), SLs enhanced the expression of , encoding a major transcription factor involved in ABA signaling. MsABI5 bound to the promoter of the gene encoding delta-1-pyrroline-5-carboxylate synthase (), upregulating its expression and thereby enhancing proline accumulation and drought resistance. In addition, MsABI5 suppressed the expression of , encoding a major transcriptional repressor involved in SL signaling. MsSMXL1 interacted with MsNAC022 instead of MsABI5 to repress the transactivation activity of MsNAC022. was upregulated by MsABI5, and MsNAC022 directly promoted expression to enhance proline accumulation and drought resistance. These findings suggest that MsSMXL1 and MsNAC022 comprise a regulatory node downstream of MsABI5 during drought stress in apple. Together, our findings suggest that in apple, SLs increase drought resistance by activating the MsABI5-MsSMXL1-MsNAC022 cascade.
干旱胁迫限制了苹果的生长、发育和产量。独脚金内酯(SLs)与脱落酸(ABA)协同作用以提高植物的抗旱性,但其协同机制尚不清楚。在此,我们确定SLs以一种与[具体基因]相关的方式促进苹果的抗旱性。在一种野生苹果品种遭受干旱胁迫期间,SLs增强了[具体基因]的表达,该基因编码一种参与ABA信号传导的主要转录因子。MsABI5与编码δ-1-吡咯啉-5-羧酸合成酶([具体基因])的基因启动子结合,上调其表达,从而增强脯氨酸积累和抗旱性。此外,MsABI5抑制了[具体基因]的表达,该基因编码一种参与SL信号传导的主要转录抑制因子。MsSMXL1与MsNAC022相互作用而非与MsABI5相互作用,以抑制MsNAC022的反式激活活性。[具体基因]被MsABI5上调,并且MsNAC022直接促进[具体基因]表达以增强脯氨酸积累和抗旱性。这些发现表明,在苹果干旱胁迫期间,MsSMXL1和MsNAC022构成了MsABI5下游的一个调控节点。总之,我们的发现表明,在苹果中,SLs通过激活MsABI5-MsSMXL1-MsNAC022级联反应来提高抗旱性。