Jo Leonardo, Buti Sara, Artur Mariana A S, Kluck Rianne M C, Cantó-Pastor Alex, Brady Siobhán M, Kajala Kaisa
Experimental & Computational Plant Development, Institute of Environmental Biology, Utrecht University, Utrecht, the Netherlands.
Laboratory of Plant Physiology, Wageningen Seed Science Centre, Wageningen University and Research, Wageningen 6708PB, the Netherlands.
J Exp Bot. 2025 Apr 17. doi: 10.1093/jxb/eraf161.
Root barrier cell types, like the endodermis and exodermis, are crucial for plant acclimation to environmental stresses. Deposition of suberin, a hydrophobic polymer, in these cell layers restricts the movement of molecules and plays a vital role in stress responses. This study investigates the role of SlMYB41, SlMYB92 and SlWRKY71 transcription factors (TFs) in regulating suberin biosynthesis in the tomato (Solanum lycopersicum) root exodermis by genetic perturbation. Genetic perturbation of these TFs altered exodermal suberin deposition patterns, indicating the SlMYBs as positive and SlWRKY71 negative regulators of suberization. RNA sequencing revealed a significant overlap between differentially expressed genes regulated by these TFs, suggesting a shared regulatory network. Gene set enrichment analyses highlighted their role in lipid and suberin biosynthesis as well as overrepresentation of exodermis-enriched transcripts. Furthermore, transactivation assays demonstrated that these two MYBs promote the expression of suberin-related genes, while SlWRKY71 represses them. These results indicate a complex antagonistic relationship, advancing our understanding of the regulatory mechanisms controlling exodermis suberization in tomato roots.
根屏障细胞类型，如内皮层和外皮层，对于植物适应环境胁迫至关重要。疏水性聚合物木栓质在这些细胞层中的沉积限制了分子的移动，并在胁迫反应中发挥着至关重要的作用。本研究通过基因干扰研究了SlMYB41、SlMYB92和SlWRKY71转录因子（TFs）在调控番茄（Solanum lycopersicum）根外皮层木栓质生物合成中的作用。这些TFs的基因干扰改变了外皮层木栓质的沉积模式，表明SlMYBs是木栓化的正调控因子，而SlWRKY71是负调控因子。RNA测序揭示了受这些TFs调控的差异表达基因之间存在显著重叠，表明存在一个共享的调控网络。基因集富集分析突出了它们在脂质和木栓质生物合成中的作用以及外皮层富集转录本的过度表达。此外，反式激活分析表明，这两个MYBs促进木栓质相关基因的表达，而SlWRKY71则抑制它们。这些结果表明存在复杂的拮抗关系，增进了我们对番茄根外皮层木栓化调控机制的理解。
